Shape memory alloy actuators and methods thereof

ABSTRACT

SMA actuators and related methods are described. One embodiment of an actuator includes a base; a plurality of buckle arms; and at least a first shape memory alloy wire coupled with a pair of buckle arms of the plurality of buckle arms. Another embodiment of an actuator includes a base and at least one bimorph actuator including a shape memory alloy material. The bimorph actuator attached to the base.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional PatentApplication 63/152,299 filed on Feb. 22, 2021 and is acontinuation-in-part application of U.S. patent application Ser. No.17/412,030, filed on Aug. 25, 2021, which is a divisional of U.S. patentapplication Ser. No. 16/775,207, filed on Jan. 28, 2020, now U.S. Pat.No. 11,105,319, which claims the benefit of U.S. Provisional PatentApplication No. 62/826,106, filed on Mar. 29, 2019 and is acontinuation-in-part of U.S. patent application Ser. No. 15/971,995,filed on May 4, 2018, now U.S. Pat. No. 10,920,755, which claims thebenefit of U.S. Provisional Patent Application No. 62/502,568, filed onMay 5, 2017 and U.S. Provisional Patent Application No. 62/650,991,filed on Mar. 30, 2018, all of which are hereby incorporated byreference in their entireties.

FIELD

Embodiments of the invention relate to the field of shape memory alloysystems. More particularly, embodiments of the invention relate to thefield of shape memory alloy actuators and methods related thereto.

BACKGROUND

Shape memory alloy (“SMA”) systems have a moving assembly or structurethat for, example, can be used in conjunction with a camera lens elementas an auto-focusing drive. These systems may be enclosed by a structuresuch as a screening can. The moving assembly is supported for movementon a support assembly by a bearing such as plural balls. The flexureelement, which is formed from metal such as phosphor bronze or stainlesssteel, has a moving plate and flexures. The flexures extend between themoving plate and the stationary support assembly and function as springsto enable the movement of the moving assembly with respect to thestationary support assembly. The balls allow the moving assembly to movewith little resistance. The moving assembly and support assembly arecoupled by four shape memory alloy (SMA) wires extending between theassemblies. Each of the SMA wires has one end attached to the supportassembly, and an opposite end attached to the moving assembly. Thesuspension is actuated by applying electrical drive signals to the SMAwires. However, these types of systems are plagued by the complexity ofthe systems that result in bulky systems that require a large foot printand a large height clearance. Further, the present systems fail toprovide high Z-stroke range with a compact, low profile footprint.

SUMMARY

SMA actuators and related methods are described. One embodiment of anactuator includes a base; a plurality of buckle arms; and at least afirst shape memory alloy wire coupled with a pair of buckle arms of theplurality of buckle arms. Another embodiment of an actuator includes abase and at least one bimorph actuator including a shape memory alloymaterial. The bimorph actuator attached to the base.

Other features and advantages of embodiments of the present inventionwill be apparent from the accompanying drawings and from the detaileddescription that follows.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present invention are illustrated by way of exampleand not limitation in the figures of the accompanying drawings, in whichlike references indicate similar elements and in which:

FIG. 1 a illustrates a lens assembly including an SMA actuatorconfigured as a buckle actuator according to an embodiment;

FIG. 1 b illustrates an SMA actuator according to an embodiment;

FIG. 2 illustrates an SMA actuator according to an embodiment;

FIG. 3 illustrates an exploded view of an autofocus assembly includingan SMA wire actuator according to an embodiment;

FIG. 4 illustrates the autofocus assembly including a SMA actuatoraccording to an embodiment;

FIG. 5 illustrates an SMA actuator according to an embodiment includinga sensor;

FIG. 6 illustrates a top view and a side view of an SMA actuatorconfigured as a buckle actuator according to an embodiment fitted with alens carriage;

FIG. 7 illustrates a side-view of a section of the SMA actuatoraccording to the embodiment;

FIG. 8 illustrates multiple views of an embodiment of a buckle actuator;

FIG. 9 illustrates a bimorph actuator according to an embodiment with alens carriage;

FIG. 10 illustrates a cutaway view of an autofocus assembly including anSMA actuator according to an embodiment;

FIGS. 11 a-c illustrates views of bimorph actuators according to someembodiments;

FIG. 12 illustrates views of an embodiment of a bimorph actuatoraccording to an embodiment;

FIG. 13 illustrates an end pad cross-section of a bimorph actuatoraccording to an embodiment;

FIG. 14 illustrates a center supply pad cross-section of a bimorphactuator according to an embodiment;

FIG. 15 illustrates an exploded view of an SMA actuator including twobuckle actuators according to an embodiment;

FIG. 16 illustrates an SMA actuator including two buckle actuatorsaccording to an embodiment;

FIG. 17 illustrates a side view of an SMA actuator including two buckleactuators according to an embodiment;

FIG. 18 illustrates a side view of an SMA actuator including two buckleactuators according to an embodiment;

FIG. 19 illustrates an exploded view of an assembly including an SMAactuator including two buckle actuator according to an embodiment;

FIG. 20 illustrates an SMA actuator including two buckle actuatorsaccording to an embodiment;

FIG. 21 illustrates an SMA actuator including two buckle actuatorsaccording to an embodiment;

FIG. 22 illustrates an SMA actuator including two buckle actuatorsaccording to an embodiment;

FIG. 23 illustrates a SMA actuator including two buckle actuators and acoupler according to an embodiment;

FIG. 24 illustrates an exploded view of an SMA system including an SMAactuator including a buckle actuator with a laminate hammock accordingto an embodiment;

FIG. 25 illustrates an SMA system including an SMA actuator including abuckle actuator 2402 with a laminate hammock according to an embodiment;

FIG. 26 illustrates a buckle actuator including a laminate hammockaccording to an embodiment;

FIG. 27 illustrates a laminate hammock of an SMA actuator according toan embodiment;

FIG. 28 illustrates a laminate formed crimp connection of an SMAactuator according to an embodiment;

FIG. 29 illustrates an SMA actuator including a buckle actuator with alaminate hammock;

FIG. 30 illustrates an exploded view of an SMA system including an SMAactuator including a buckle actuator according to an embodiment;

FIG. 31 illustrates an SMA system including an SMA actuator including abuckle actuator according to an embodiment;

FIG. 32 illustrates an SMA actuator including a buckle actuatoraccording to an embodiment;

FIG. 33 illustrates a two yoke capture joint of a pair of buckle arms ofan SMA actuator according to an embodiment;

FIG. 34 illustrates a resistance weld crimp for an SMA actuatoraccording to an embodiment used to attach an SMA wire to the buckleactuator;

FIG. 35 illustrates an SMA actuator including a buckle actuator with atwo yoke capture joint;

FIG. 36 illustrates a SMA bimorph liquid lens according to anembodiment;

FIG. 37 illustrates a perspective SMA bimorph liquid lens according toan embodiment;

FIG. 38 illustrates a cross-section and a bottom view of SMA bimorphliquid lens according to an embodiment;

FIG. 39 illustrates an SMA system including an SMA actuator with bimorphactuators according to an embodiment;

FIG. 40 illustrates the SMA actuator with bimorph actuators according toan embodiment;

FIG. 41 illustrates the length of a bimorph actuator and the location ofa bonding pad for an SMA wire to extend the wire length beyond thebimorph actuator;

FIG. 42 illustrates an exploded view of an SMA system including anbimorph actuator according to an embodiment;

FIG. 43 illustrates an exploded view of a subsection of the SMA actuatoraccording to an embodiment;

FIG. 44 illustrates a subsection of the SMA actuator according to anembodiment;

FIG. 45 illustrates a 5 axis sensor shift system according to anembodiment;

FIG. 46 illustrates an exploded view of a 5 axis sensor shift systemaccording to an embodiment;

FIG. 47 illustrates an SMA actuator including bimorph actuatorsintegrated into this circuit for all motion according to an embodiment;

FIG. 48 illustrates an SMA actuator including bimorph actuatorsintegrated into this circuit for all motion according to an embodiment;

FIG. 49 illustrates a cross section of a 5 axis sensor shift systemaccording to an embodiment;

FIG. 50 illustrates an SMA actuator according to an embodiment includingbimorph actuators;

FIG. 51 illustrates a top view of an SMA actuator according to anembodiment including bimorph actuators that moved an image sensor indifferent x and y positions;

FIG. 52 illustrates an SMA actuator including bimorph actuatorsaccording to an embodiment configured as a box bimorph autofocus;

FIG. 53 illustrates an SMA actuator including bimorph actuatorsaccording to an embodiment;

FIG. 54 illustrates an SMA actuator including bimorph actuatorsaccording to an embodiment;

FIG. 55 illustrates an SMA actuator including bimorph actuatorsaccording to an embodiment;

FIG. 56 illustrates a SMA system including a SMA actuator according toan embodiment including bimorph actuators;

FIG. 57 illustrates an exploded view of SMA system including a SMAactuator according to an embodiment including bimorph actuatorsconfigured as a two axis lens shift OIS;

FIG. 58 illustrates a cross-section of SMA system including a SMAactuator according to an embodiment including bimorph actuatorsconfigured as a two axis lens shift OIS;

FIG. 59 illustrates a box bimorph actuator according to an embodiment;

FIG. 60 illustrates a SMA system including a SMA actuator according toan embodiment including bimorph actuators;

FIG. 61 illustrates an exploded view of SMA system including a SMAactuator according to an embodiment including bimorph actuators;

FIG. 62 illustrates a cross-section of SMA system including a SMAactuator according to an embodiment including bimorph actuators;

FIG. 63 illustrates box bimorph actuator according to an embodiment;

FIG. 64 illustrates a SMA system including a SMA actuator according toan embodiment including bimorph actuators;

FIG. 65 illustrates an exploded view of a SMA system including a SMAactuator according to an embodiment including bimorph actuators;

FIG. 66 illustrates a SMA system including a SMA actuator according toan embodiment including bimorph actuators;

FIG. 67 illustrates a SMA system including a SMA actuator according toan embodiment including bimorph actuators;

FIG. 68 illustrates a SMA system including a SMA actuator according toan embodiment including bimorph actuators;

FIG. 69 illustrates an exploded view of SMA including a SMA actuatoraccording to an embodiment including bimorph actuators;

FIG. 70 illustrates a cross-section of SMA system including a SMAactuator according to an embodiment including bimorph actuatorsconfigured as a three axis sensor shift OIS;

FIG. 71 illustrates a box bimorph actuator component according to anembodiment;

FIG. 72 illustrates a flexible sensor circuit for use in a SMA systemaccording to an embodiment;

FIG. 73 illustrates a SMA system including a SMA actuator according toan embodiment including bimorph actuators;

FIG. 74 illustrates an exploded view of SMA system including a SMAactuator according to an embodiment including bimorph actuators;

FIG. 75 illustrates a cross-section of SMA system including a SMAactuator according to an embodiment;

FIG. 76 illustrates box bimorph actuator according to an embodiment;

FIG. 77 illustrates a flexible sensor circuit for use in a SMA systemaccording to an embodiment;

FIG. 78 illustrates a SMA system including a SMA actuator according toan embodiment including bimorph actuators;

FIG. 79 illustrates an exploded view of SMA system including a SMAactuator according to an embodiment including bimorph actuators;

FIG. 80 illustrates a cross-section of SMA system including a SMAactuator according to an embodiment;

FIG. 81 illustrates box bimorph actuator according to an embodiment;

FIG. 82 illustrates a flexible sensor circuit for use in a SMA systemaccording to an embodiment;

FIG. 83 illustrates a SMA system including a SMA actuator according toan embodiment including bimorph actuators;

FIG. 84 illustrates an exploded view of SMA system including a SMAactuator according to an embodiment;

FIG. 85 illustrates a cross-section of SMA system including a SMAactuator according to an embodiment including bimorph actuators;

FIG. 86 illustrates box bimorph actuator for use in a SMA systemaccording to an embodiment;

FIG. 87 illustrates a flexible sensor circuit for use in a SMA systemaccording to an embodiment;

FIG. 88 illustrates exemplary dimensions for a bimorph actuator of anSMA actuator according to embodiments;

FIG. 89 illustrates a lens system for a folded camera according to anembodiment;

FIG. 90 illustrates several embodiments of a lens system includingliquid lenses according to an embodiment;

FIG. 91 illustrates a folding lens that is a prism, which is disposed onan actuator, according to an embodiment;

FIG. 92 illustrates a bimorph arm with an offset according to anembodiment;

FIG. 93 illustrates a bimorph arm with an offset and a limiter accordingto an embodiment;

FIG. 94 illustrates a bimorph arm with an offset and a limiter accordingto an embodiment;

FIG. 95 illustrates an embodiment of a base including a bimorph arm withan offset according to an embodiment;

FIG. 96 illustrates an embodiment of a base including two bimorph armswith an offset according to an embodiment;

FIG. 97 illustrates a buckler arm including load point extensionsaccording to an embodiment;

FIG. 98 illustrates a buckler arm 9801 including load point extensions9810 according to an embodiment;

FIG. 99 illustrates a bimorph arm including load point extensionsaccording to an embodiment;

FIG. 100 illustrates a bimorph arm including load point extensionsaccording to an embodiment;

FIG. 101 illustrates an SMA optical image stabilizer according to anembodiment;

FIG. 102 illustrates an SMA material attach portion 40 of a movingportion according to an embodiment;

FIG. 103 illustrates an SMA attach portion of a static plate withresistance welded SMA wires attached thereto according to an embodiment;

FIG. 104 illustrates an SMA actuator 45 including a buckle actuatoraccording to an embodiment;

FIGS. 105 a-b illustrate a resistance weld crimp including an island foran SMA actuator according to an embodiment;

FIG. 106 illustrates the relationship between the bend plane z offset,the trough width, and the peak force of a bimorph beam according to anembodiment;

FIG. 107 illustrates examples of how a box volume which is anapproximation of a box that encompasses the entire bimorph actuatoraccording to an embodiment is related to the work per bimorph component;

FIG. 108 illustrates a liquid lens actuated using buckler actuatorsaccording to an embodiment;

FIG. 109 illustrates an unfixed, load point end of a bimorph armaccording to an embodiment;

FIG. 110 illustrates an unfixed, load point end of a bimorph armaccording to an embodiment;

FIG. 111 illustrates an unfixed, load point end of a bimorph armaccording to an embodiment;

FIG. 112 illustrates an unfixed, load point end of a bimorph armaccording to an embodiment;

FIG. 113 illustrates a fixed end of a bimorph arm according to anembodiment;

FIG. 114 illustrates a fixed end of a bimorph arm according to anembodiment;

FIG. 115 illustrates a fixed end of a bimorph arm according to anembodiment;

FIG. 116 illustrates a fixed end of a bimorph arm according to anembodiment;

FIG. 117 illustrates a backside view of a fixed end of a bimorph armaccording to an embodiment;

FIG. 118 illustrates an unfixed, load point end of a bimorph armaccording to an embodiment;

FIG. 119 illustrates an unfixed, load point end of a bimorph armaccording to an alternative embodiment;

FIG. 120 illustrates an unfixed, load point end of a bimorph armaccording to an alternative embodiment;

FIG. 121 illustrates an unfixed, load point end of a bimorph armaccording to an alternative embodiment;

FIG. 122 illustrates an unfixed, load point end of a bimorph armaccording to an alternative embodiment;

FIG. 123 illustrates a fixed end of a bimorph arm according to anembodiment;

FIG. 124 illustrates a fixed end of a bimorph arm according to anembodiment;

FIG. 125 illustrates a fixed end of a bimorph arm according to anembodiment;

FIG. 126 illustrates a balanced bimorph actuator according to anembodiment including two bimorph arms arranged in an staggeredorientation;

FIG. 127 illustrates an optical image stabilization including balancedbimorph actuators according to an embodiment;

FIG. 128 illustrates a balanced bimorph actuator according to anembodiment including two bimorph arms arranged in an in-lineorientation;

FIG. 129 illustrates a top view of a balanced bimorph actuator accordingto an embodiment including two bimorph arms arranged in an in-lineorientation;

FIG. 130 illustrates a top view of a balanced bimorph actuator accordingto an embodiment including a common base island;

FIG. 131 illustrates a side view of a balanced bimorph actuatoraccording to an embodiment including two bimorph arms arranged in areversed in-line orientation;

FIG. 132 illustrates a top view of a balanced bimorph actuator accordingto an embodiment including two bimorph arms arranged in a reversedin-line orientation;

FIG. 133 illustrates a top view of a balanced bimorph actuator accordingto an embodiment including two bimorph arms arranged in a reversedin-line orientation;

FIG. 134 illustrates a balanced bimorph actuator according to anembodiment including two bimorph arms arranged in an inline orientation;

FIG. 135 illustrates a top view of a balanced bimorph actuator accordingto an embodiment including two bimorph arms arranged in an in-lineorientation;

FIG. 136 illustrates a top view of a balanced bimorph actuator accordingto an embodiment including two bimorph arms arranged in an in-lineorientation;

FIG. 137 illustrates a balanced bimorph actuator according to anembodiment including two bimorph arms arranged in an staggeredorientation;

FIG. 138 illustrates a top view of a balanced bimorph actuator accordingto an embodiment including two bimorph arms arranged in an staggeredorientation;

FIG. 139 illustrates a top view of a balanced bimorph actuator accordingto an embodiment including two bimorph arms arranged in an staggeredorientation;

FIG. 140 illustrates an optical image stabilization system includingbalanced bimorph actuators according to an embodiment;

FIG. 141 illustrates an exploded view of an optical image stabilizationsystem including balanced bimorph actuators according to an embodiment;

FIG. 142 illustrates an optical image stabilization system includingbalanced bimorph actuators according to an embodiment;

FIG. 143 illustrates a sensor shift optical image stabilization systemincluding bimorph actuators according to an embodiment;

FIG. 144 illustrates an optical image stabilization system includingbalanced bimorph actuators according to an embodiment;

FIG. 145 illustrates an outer housing of an optical image stabilizationsystem according to an embodiment;

FIG. 146 illustrates a cross section of an optical image stabilizationsystem including an outer housing according to an embodiment;

FIG. 147 illustrates an exploded view of an optical image stabilizationsystem including flat spring circuits according to an embodiment;

FIG. 148 illustrates a cross section on an optical image stabilizationsystem including flat spring circuits according to an embodiment;

FIG. 149 illustrates a base including springs according to anembodiment;

FIG. 150 illustrates a flat spring circuit according to an embodiment;and

FIG. 151 illustrates a bimorph actuator including a crimp according toan embodiment.

DETAILED DESCRIPTION

Embodiments of an SMA actuator are described herein that include acompact footprint and providing a high actuation height, for examplemovement in the positive z-axis direction (z-direction), referred toherein as the z-stroke. Embodiments of the SMA actuator include an SMAbuckle actuator and an SMA bimorph actuator. The SMA actuator may beused in many applications including, but not limited to, a lens assemblyas an autofocus actuator, a micro-fluidic pump, a sensor shift, opticalimage stabilization, optical zoom assembly, to mechanically strike twosurfaces to create vibration sensations typically found in hapticfeedback sensors and devices, and other systems where an actuator isused. For example, embodiments of an actuator described herein could beused as a haptic feedback actuator for use in cellphones or wearabledevices configured to provide the user an alarm, notification, alert,touched area or pressed button response. Further, more than one SMAactuator could be used in a system to achieve a larger stroke.

For various embodiments, the SMA actuator has a z-stroke that is greaterthan 0.4 millimeters. Further, the SMA actuator for various embodimentshas a height in the z-direction of 2.2 millimeters or less, when the SMAactuator is in its initial, a de-actuated position. Various embodimentsof the SMA actuator configured as an autofocus actuator in a lensassembly may have a footprint as small as 3 millimeters greater than thelens inner diameter (“ID”). According to various embodiments, the SMAactuator may have a footprint that is wider in one direction toaccommodate components including, but not limited to, sensors, wires,traces, and connectors. According to some embodiments, the footprint ofan SMA actuator is 0.5 millimeters greater in one direction, for examplethe length of the SMA actuator is 0.5 millimeters greater than thewidth.

FIG. 1 a illustrates a lens assembly including an SMA actuatorconfigured as a buckle actuator according to an embodiment. FIG. 1 billustrates an SMA actuator configured as a buckle actuator according toan embodiment. The buckle actuators 102 are coupled with a base 101. Asillustrated in FIG. 1 b , SMA wires 100 are attached to buckle actuators102 such that when the SMA wires 100 are actuated and contract thiscauses the buckle actuators 102 to buckle, which results in at least thecenter portion 104 of each buckle actuator 102 to move in the z-strokedirection, for example the positive z-direction, as indicated by thearrows 108. According to some embodiments, the SMA wires 100 areactuated when electrical current is supplied to one end of the wirethrough a wire retainer such as a crimp structure 106. The current flowsthrough the SMA wire 100 heating it due to the resistance inherent inthe SMA material of which the SMA wire 100 is made. The other side ofthe SMA wire 100 has a wire retainer such as a crimp structure 106 thatconnects the SMA wire 100 to complete the circuit to ground. Heating ofthe SMA wire 100 to a sufficient temperature causes the unique materialproperties to change from martensite to austenite crystalline structure,which causes a length change in the wire. Changing the electricalcurrent changes the temperature and therefore changes the length of thewire, which is used to actuate and de-actuate the actuator to controlthe movement of the actuator in at least the z-direction. One skilled inthe art would understand that other techniques could be used to provideelectrical current to an SMA wire.

FIG. 2 illustrates an SMA actuator configured as an SMA bimorph actuatoraccording to an embodiment. As illustrated in FIG. 2 , the SMA actuatorincludes bimorph actuators 202 coupled with a base 204. The bimorphactuators 202 include an SMA ribbon 206. The bimorph actuators 202 areconfigured to move at least the unfixed ends of the bimorph actuators202 in the z-stroke direction 208 as the SMA ribbon 206 shrinks.

FIG. 3 illustrates an exploded view of an autofocus assembly includingan SMA actuator according to an embodiment. As illustrated, an SMAactuator 302 is configured as a buckle actuator according to embodimentsdescribed herein. The autofocus assembly also includes optical imagestabilization (“OIS”) 304, a lens carriage 306 configured to hold one ormore optical lens using techniques including those known in the art, areturn spring 308, a vertical slide bearing 310, and a guide cover 312.The lens carriage 306 is configured to slide against the vertical slidebearing 310 as the SMA actuator 302 moves in the z-stroke direction, forexample the positive z-direction, when the SMA wires are actuated andpull and buckle the buckle actuators 302 using techniques includingthose described herein. The return spring 308 is configured to apply aforce in the opposite direction to the z-stroke direction on the lenscarriage 306 using techniques including those known in the art. Thereturn spring 308 is configured, according to various embodiments, tomove the lens carriage 306 in the opposite direction of the z-strokedirection when the tension in the SMA wires is lowered as the SMA wireis de-actuated. When the tension in the SMA wires is lowered to theinitial value, the lens carriage 306 moves to the lowest height in thez-stroke direction. FIG. 4 illustrates the autofocus assembly includingan SMA wire actuator according to an embodiment illustrated in FIG. 3 .

FIG. 5 illustrates an SMA wire actuator according to an embodimentincluding a sensor. For various embodiments, the sensor 502 isconfigured to measure the movement of the SMA actuator in thez-direction or the movement of a component that that SMA actuator ismoving using techniques including those known in the art. The SMAactuator including one or more buckle actuators 506 configured toactuate using one or more SMA wires 508 similar to those describedherein. For example, in the autofocus assembly described in reference toFIG. 4 , the sensor is configured to determine the amount of movementthe lens carriage 306 moves in the z-direction 504 from an initialposition using techniques including those known in the art. According tosome embodiments, the sensor is a tunnel magneto resistance (“TMR”)sensor.

FIG. 6 illustrates a top view and a side view of an SMA actuator 602configured as a buckle actuator according to an embodiment fitted with alens carriage 604. FIG. 7 illustrates a side-view of a section of theSMA actuator 602 according to the embodiment illustrated in FIG. 6 .According to the embodiment illustrated in FIG. 7 , the SMA actuator 602includes a slide base 702. According to an embodiment, the slide base702 is formed of metal, such as stainless steel, using techniquesincluding those know in the art. However, one skilled in the art wouldunderstand that other materials could be used to form the slide base702. Further, the slide base 702, according to some embodiments, hasspring arms 612 coupled with the SMA actuator 602. According to variousembodiments, spring arms 612 are configured to serve two functions. Thefirst function is to help push on an object, for example a lens carriage604, into a guide cover's vertical slide surface. For this example, thespring arms 612 preload the lens carriage 604 up against this surfaceensuring that the lens will not tilt during actuation. For someembodiments, the vertical slide surfaces 708 are configured to mate withthe guide cover. The second function of the spring arms 612 is to helppull the SMA actuator 602 back down, for example in the negativez-direction, after the SMA wires 608 move the SMA actuator 602 in thez-stroke direction, the positive z-direction. Thus, when the SMA wires608 are actuated they contract to move the SMA actuator 602 in thez-stroke direction and the spring arms 612 are configured to move theSMA actuator 602 in the opposite direction of the z-stroke directionwhen the SMA wires 608 are de-actuated.

The SMA actuator 602 also includes a buckle actuator 710. For variousembodiments, the buckle actuator 710 is formed of metal, such asstainless steel. Further, the buckle actuator 710 includes buckle arms610 and one or more wire retainers 606. According to the embodimentillustrated in FIGS. 6 and 7 , the buckle actuator 710 includes fourwire retainers 606. The four wire retainers 606 are each configured toreceive an end of an SMA wire 608 and retain the end of the SMA wire608, such that the SMA wire 608 is affixed to the buckle actuator 710.For various embodiments, the four wire retainers 606 are crimps that areconfigured to clamp down on a portion of the SMA wire 608 to affix thewire to the crimp. One skilled in the art would understand that an SMAwire 608 may be affixed to a wire retainer 606 using techniques known inthe art including, but not limited to, adhesive, solder, andmechanically affixed. The smart memory alloy (“SMA”) wires 608 extendbetween a pair of wire retainers 606 such that the buckle arms 610 ofthe buckle actuator 710 are configured to move when the SMA wires 608are actuated which results in the pair of wire retainers 606 beingpulled closer together. According to various embodiments, the SMA wires608 are electrically actuated to move and control the position of thebuckle arms 610 when a current is applied to the SMA wire 608. The SMAwire 608 is de-actuated when the electrical current is removed or belowa threshold. This moves the pair of wire retainers 606 apart and thebuckle arms 610 move in the opposite direction of that when the SMA wire608 is actuated. According to various embodiments, the buckle arms 610are configured to have an initial angle of 5 degrees with respect to theslide base 702 when the SMA wire is de-actuated in its initial position.And, at full stroke or when the SMA wire is fully actuated the bucklearms 610 are configured to have an angle of 10 to 12 degrees withrespect to the slide base 702 according to various embodiments.

According to the embodiment illustrated in FIGS. 6 and 7 , the SMAactuator 602 also includes slide bearings 706 configured between theslide base 702 and the wire retainers 606. The slide bearings 706 areconfigured to minimize any friction between the slide base 702 and abuckle arm 610 and/or a wire retainer 606. The slide bearings for someembodiments are affixed to the wire retainer 606. According to variousembodiments the slide bearings are formed of polyoxymethylene (“POM”).One skilled in the art would understand that other structures could beused to lower any friction between the buckle actuator and the base.

According to various embodiments, the slide base 702 is configured tocouple with an assembly base 704 such as an autofocus base for anautofocus assembly. The actuator base 704, according to someembodiments, includes an etched shim. Such an etched shim may be used toprovide clearance for wires and crimps when the SMA actuator 602 is partof an assembly, such as an autofocus assembly.

FIG. 8 illustrates multiple views of an embodiment of a buckle actuator802 with respect to an x-axis, a y-axis, and a z-axis. As oriented inFIG. 8 , the buckle arms 804 are configured to move in the z-axis whenthe SMA wires are actuated and de-actuated as described herein.According to the embodiment illustrated in FIG. 8 , the buckle arms 804are coupled with each other through a center portion such as a hammockportion 806. A hammock portion 806, according to various embodiments, isconfigured to cradle a portion of an object that is acted upon by thebuckle actuator, for example a lens carriage that is moved by the buckleactuator using techniques including those described herein. A hammockportion 806 is configured to provide lateral stiffness to the buckleactuator during actuation according to some embodiments. For otherembodiments, a buckle actuator does not include a hammock portion 806.According to these embodiments, the buckle arms are configured to act onan object to move it. For example, the buckle arms are configured to actdirectly on features of a lens carriage to push it upward.

FIG. 9 illustrates an SMA actuator configured as an SMA bimorph actuatoraccording to an embodiment. The SMA bimorph actuator includes bimorphactuators 902 including those described herein. According to theembodiment illustrated in FIG. 9 , one end 906 of each of bimorphactuators 902 is affixed to a base 908. According to some embodiments,the one end 906 is welded to base 908. However, one skilled in the artwould understand other techniques could be used to affix the one end 906to the base 908. FIG. 9 also illustrates a lens carriage 904 arrangedsuch that the bimorph actuators 902 are configured to curl in thez-direction when actuated and lift the carriage 904 in the z-direction.For some embodiments, a return spring is used to push the bimorphactuators 902 back to an initial position. A return spring may beconfigured as described herein to aide in pushing the bimorph actuatordown to their initial, de-actuated positions. Because of the smallfootprint of the bimorph actuators, SMA actuators can be made that havea reduced footprint over current actuator technologies.

FIG. 10 illustrates a cutaway view of an autofocus assembly including anSMA actuator according to an embodiment that includes a position sensor,such as a TMR sensor. The autofocus assembly 1002 includes a positionsensor 1004 attached to a moving spring 1006, and a magnet 1008 attachedto a lens carriage 1010 of an autofocus assembly including an SMAactuator, such as those described herein. The position sensor 1004 isconfigured to determine the amount of movement the lens carriage 1010moves in the z-direction 1005 from an initial position based on adistance that the magnet 1008 is from the position sensor 1004 usingtechniques including those known in the art. According to someembodiments, the position sensor 1004 is electrically coupled with acontroller or a processor, such as a central processing unit, using aplurality of electrical traces on a spring arm of a moving spring 1006of an optical image stabilization assembly.

FIGS. 11 a-c illustrates views of bimorph actuators according to someembodiments. According to various embodiments, a bimorph actuator 1102includes a beam 1104 and one or more SMA materials 1106 such as an SMAribbon 1106 b (e.g., as illustrated in a perspective view of a bimorphactuator including an SMA ribbon according to the embodiment of FIG. 11b ) or SMA wire 1106 a (e.g., as illustrated in a cross-section of abimorph actuator including an SMA wire according to the embodiment ofFIG. 11 a ). The SMA material 1106 is affixed to the beam 1104 usingtechniques including those describe herein. According to someembodiments, the SMA material 1106 is affixed to a beam 1104 usingadhesive film material 1108. Ends of the SMA material 1106, for variousembodiments, are electrically and mechanically coupled with contacts1110 configured to supply current to the SMA material 1106 usingtechniques including those known in the art. The contacts 1110 (e.g., asillustrated in FIGS. 11 a and 11 b ), according to various embodiments,are gold plated copper pads. According to embodiments, a bimorphactuator 1102 having a length of approximately 1 millimeter areconfigured to generate a large stroke and push forces of 50 millinewtons(“mN”) is used as part of a lens assembly, for example as illustrated inFIG. 11 c . According to some embodiments, the use of a bimorph actuator1102 having a length greater than 1 millimeter will generate more strokebut less force than that having a length of 1 millimeter. For anembodiment, a bimorph actuator 1102 includes a 20 micrometer thick SMAmaterial 1106, a 20 micrometer thick insulator 1112, such as a polyimideinsulator, and a 30 micrometer thick stainless steel beam 1104 or basemetal. Various embodiments include a second insulator disposed between acontact layer including the contacts 1110 and the SMA material 1106. Thesecond insulator is configured, according to some embodiments, toinsulate the SMA material 1106 from portions of the contact layer notused as the contacts 1110. For some embodiments, the second insulator isa covercoat layer, such a polyimide insulator. One skilled in the artwould understand that other dimensions and materials could be used tomeet desired design characteristics.

FIG. 12 illustrates views of an embodiment of a bimorph actuatoraccording to an embodiment. The embodiment as illustrated in FIG. 12includes a center feed 1204 for applying power. Power is supplied at thecenter of the SMA material 1202 (wire or ribbon), such as that describedherein. Ends of the SMA material 1202 are grounded to the beam 1206 orbase metal as a return path at the end pads 1203. The end pads 1203 areelectrically isolated from the rest of the contact layer 1214. Accordingto embodiments, the close proximity of a beam 1206 or base metal to theSMA material 1202, such as an SMA wire, along the entire length of theSMA material 1202 provides faster cooling of the wire when current isturned off, that is the bimorph actuator is de-actuated. The result is afaster wire deactivation and actuator response time. The thermal profileof the SMA wire or ribbon is improved. For example, the thermal profileis more uniform such that a higher total current can be reliablydelivered to the wire. Without a uniform heat sink, portions of thewire, such as a center region, may overheated and be damaged thusrequiring a reduced current and reduced motion to reliably operate. Thecenter feed 1204 provides the benefits of quicker wireactivation/actuation (faster heating) and reduced power consumption(lower resistance path length) of the SMA material 1202 for fasterresponse time. This allows a faster actuator motion and capability tooperate at a higher movement frequency.

As illustrated in FIG. 12 , the beam 1206 includes a center metal 1208that is isolated from the rest of the beam 1206 to form the center feed1204. An insulator 1210, such as those described herein, is disposedover the beam 1206. The insulator 1210 is configured to have one or moreopenings or vias 1212 to provide electrical access to the beam 1206, forexample to couple a ground section 1214 b of the contact layer, and toprovide contact to the center metal 1208 to form the center feed 1204. Acontact layer 1214, such as those described herein, includes a powersection 1214 a and a ground section 1214 b, according to someembodiments, to provide actuation/control signals to the bimorphactuator by way of a power supply contact 1216 and a ground contact1218. A covercoat layer 1220, such as those described herein, isdisposed over the contact layer 1214 to electrically isolate the contactlayer except at portions of the contact layer 1214 where electricalcoupling is desired (e.g., one or more contacts).

FIG. 13 illustrates an end pad cross-section of a bimorph actuatoraccording to an embodiment as illustrated in FIG. 12 . As describedabove, the end pad 1203 electrically isolated from the rest of thecontact layer 1214 by way of a gap 1222 formed between the end pad 1203and the contact layer 1214. The gap is formed, according to someembodiments, using etching techniques including those known in the art.The end pad 1203 includes a via section 1224 configured to electricallycouple the end pad 1203 with the beam 1206. The via section 1224 formedin a via 1212 formed in the insulator 1210. The SMA material 1202 iselectrically coupled to the end pad 1203. The SMA material 1202 can beelectrically coupled to the end pad 1203 using technique including, butnot limited to, solder, resistance welding, laser welding, and directplating.

FIG. 14 illustrates a center feed cross-section of a bimorph actuatoraccording to an embodiment as illustrated in FIG. 12 . The center feed1204 is electrically coupled with to a power supply through the contactlayer 1214 and electrically and thermally coupled with the center metal1208 by way of a via section 1224 in the center feed 1204 formed in avia 1212 formed in the insulator 1210.

The actuators described herein could be used to form an actuatorassembly that uses multiple buckle and or multiple bimorph actuators.According to an embodiment, the actuators may be stacked on top of eachother in order to increase a stroke distance that can be achieved.

FIG. 15 illustrates an exploded view of an SMA actuator including twobuckle actuators according to an embodiment. Two buckle actuators 1302,1304, according to embodiments described herein, are arranged withrespect to each other to use their motion to oppose each other. Forvarious embodiments, the two buckle actuators 1302, 1304 are configuredto move in an inverse relation to each other to position a lens carriage1306. For example, the first buckle actuator 1302 is configured toreceive an inverse power signal of the power signal sent to the secondbuckle actuator 1304.

FIG. 16 illustrates an SMA actuator including two buckle actuatorsaccording to an embodiment. The buckle actuators 1302, 1304 areconfigured such that the buckle arms 1310, 1312 of each buckle actuator1302, 1304 face each other and the slide base 1314, 1316 of each buckleactuator 1302, 1304 are an outer surface of the two buckle actuators. Ahammock portion 1308 of each SMA actuators 1302, 1304, according tovarious embodiments, is configured to cradle a portion of an object thatis acted upon by the one or more buckle actuators 1302, 1304, forexample a lens carriage 1306 that is moved by the buckle actuators usingtechniques including those described herein.

FIG. 17 illustrates a side view of an SMA actuator including two buckleactuators according to an embodiment that illustrates the direction ofthe SMA wires 1318 that result in moving an object such as a lenscarriage in a positive z direction or in an upwardly direction.

FIG. 18 illustrates a side view of an SMA actuator including two buckleactuators according to an embodiment that illustrates the direction ofthe SMA wires 1318 that result in moving an object such as a lenscarriage in a negative z direction or in a downwardly direction.

FIG. 19 illustrates an exploded view an assembly including an SMAactuator including two buckle actuators according to an embodiment. Thebuckle actuators 1902, 1904 are configured such that the buckle arms1910, 1912 of each buckle actuator 1902, 1904 are an outer surface ofthe two buckle actuators and the slide base 1914, 1916 of each buckleactuator 1902, 1904 face each other. A hammock portion 1908 of each SMAactuators 1902, 1904, according to various embodiments, is configured tocradle a portion of an object that is acted upon by the one or morebuckle actuators 1902, 1904, for example a lens carriage 1906 that ismoved by the buckle actuators using techniques including those describedherein. For some embodiments, the SMA actuator includes a base portion1918 configured to receive the second buckle actuator 1904. The SMAactuator may also include a cover portion 1920. FIG. 20 illustrates anSMA actuator including two buckle actuators according to an embodimentincluding a base portion and a cover portion.

FIG. 21 illustrates an SMA actuator including two buckle actuatorsaccording to an embodiment. For some embodiments, the buckle actuators1902, 1904 are arranged with respect to each other such that the hammockportions 1908 of the first buckle actuator 1902 are rotated about 90degrees from the hammock portions of the second buckle actuator 1904.The 90 degrees configuration enables pitch and roll rotation of anobject, such as a lens carriage 1906. This provides better control overthe movement of the lens carriage 1906. For various embodiments,differential power signals are applied to the SMA wires of each buckleactuator pair, which provides for pitch and roll rotation of the lenscarriage for tilt OIS motion.

Embodiments of the SMA actuators including two buckle actuators removethe need to have a return spring. The use of two buckle actuators canimprove/reduce hysteresis when using SMA wire resistance for positionalfeedback. The opposing force SMA actuators including two buckleactuators aid in more accurate position control due to lower hysteresisthan those including a return spring. For some embodiments, such as theembodiment illustrated in FIG. 22 , the SMA actuator including twobuckle actuators 2202, 2204 provide 2-axis tilt using differential powerto the left and right SMA wires 2218 a, 2218 b of each buckle actuator2202, 2204. For example, a left SMA wire 2218 a is actuated with higherpower than a right SMA wire 2218 b. This causes the left side of thelens carriage 2206 to move down and right side to move up (tilt). TheSMA wires of the first buckle actuator 2202 are held at equal power, forsome embodiments, to act as a fulcrum for the SMA wires 2218 a, 2218 bto differentially push against to cause tilt motion. Reversing the powersignals applied to the SMA wires, for example applying equal power tothe SMA wires of the second buckle actuator 2204 and using differentialpower to the left and right SMA wires 2218 a, 2218 b of the secondbuckle actuator 2204 results in a tilt of the lens carriage 2206 in theother direction. This provides the ability to tilt an object, such as alens carrier, in either axis of motion or can tune out any tilt betweenthe lens and sensor for good dynamic tilt, which leads to better picturequality across all pixels.

FIG. 23 illustrates a SMA actuator including two buckle actuators and acoupler according to an embodiment. The SMA actuator includes two buckleactuators such as those described herein. A first buckle actuator 2302is configured to couple with a second buckle actuator 2304 using acoupler, such as a coupler ring 2305. The buckle actuators 2302, 2304are arranged with respect to each other such that the hammock portions2308 of the first buckle actuator 2302 are rotated about 90 degrees fromthe hammock portions 2309 of the second buckle actuator 2304. A payloadfor moving, such as a lens or lens assembly, is attached to a lenscarriage 2306 configured to be disposed on a slide base of first buckleactuator 2302.

For various embodiments, equal power can be applied to the SMA wires ofthe first buckle actuator 2302 and the second buckle actuator 2304. Thiscan result in maximizing the z stroke of the SMA actuator in thepositive z-direction. For some embodiments, the stroke of the SMAactuator can have a z stroke equal to or greater than two times thestroke of other SMA actuators including two buckle actuators. For someembodiments, an additional spring can be added to the two buckleactuators to push against to aid in pushing the actuator assembly andthe payload back down when the power signals are removed from the SMAactuator. Equal and opposite power signals can be applied to the SMAwires of the first buckle actuator 2302 and the second buckle actuator2304. This enables the SMA actuator to be moved in the positivez-direction by a buckle actuator and to be moved in the negativez-direction by a buckle actuator, which enables accurate control of theposition of the SMA actuator. Further, equal and opposite power signals(differential power signals) can be applied to the left and right SMAwire of the first buckle actuator 2302 and the second buckle actuator2304 to tilt an object, such as a lens carriage 2306 in the direction ofat least one of two axis.

Embodiments of SMA actuator including the two buckle actuators and acoupler, such as that illustrated in FIG. 23 , can be coupled with anadditional buckle actuator and pairs of buckle actuators to achieve adesired stroke greater than that of the single SMA actuator.

FIG. 24 illustrates an exploded view of an SMA system including an SMAactuator including a buckle actuator with a laminate hammock accordingto an embodiment. As described herein, SMA systems, for someembodiments, are configured to be used in conjunction with one or morecamera lens elements as an auto-focusing drive. As illustrated in FIG.24 , the SMA system includes a return spring 2403 configured, accordingto various embodiments, to move a lens carriage 2405 in the oppositedirection of the z-stroke direction when the tension in the SMA wires2408 is lowered as the SMA wire is de-actuated. The SMA system for someembodiments includes a housing 2409 configured to receive the returnspring 2403 and to act a slide bearing to guide the lens carriage in thez-stroke direction. The housing 2409 is also configured to be disposedon the buckle actuator 2402. The buckle actuator 2402 includes a slidebase 2401 similar to those described herein. The buckle actuator 2402includes buckle arms 2404 coupled with a hammock portion, such as alaminated hammock 2406 formed of a laminate. The buckle actuator 2402also includes a SMA wire attach structures such as a laminate formedcrimp connection 2412.

As illustrated in FIG. 24 , the slide base 2401 is disposed on anoptional adaptor plate 2414. The adaptor plate is configured to mate theSMA system or the buckle actuator 2402 to another system, such as anOIS, additional SMA systems, or other components. FIG. 25 illustrates anSMA system 2501 including an SMA actuator including a buckle actuator2402 with a laminate hammock according to an embodiment.

FIG. 26 illustrates a buckle actuator including a laminate hammockaccording to an embodiment. The buckle actuator 2402 includes bucklearms 2404. The buckle arms 2404 are configured to move in the z-axiswhen the SMA wires 2408 are actuated and de-actuated as describedherein. The SMA wires 2408 are attached to the buckle actuator usinglaminate formed crimp connections 2412. According to the embodimentillustrated in FIG. 26 , the buckle arms 2404 are coupled with eachother through a center portion such as a laminate hammock 2406. Alaminate hammock 2406, according to various embodiments, is configuredto cradle a portion of an object that is acted upon by the buckleactuator, for example a lens carriage that is moved by the buckleactuator using techniques including those described herein.

FIG. 27 illustrates a laminate hammock of an SMA actuator according toan embodiment. For some embodiments, the laminate hammock 2406 materialis a low stiffness material so it does not resist the actuation motion.For example, the laminate hammock 2406 is formed using a copper layerdisposed on a first polyimide layer with a second polyimide layerdisposed on the copper. For some embodiments, the laminate hammock 2406is formed on buckle arms 2404 using deposition and etching techniquesincluding those known in the art. For other embodiments, the laminatehammock 2406 is formed separately from the buckle arms 2404 and attachedto the buckle arms 2404 using techniques including welding, adhesive,and other techniques known in the art. For various embodiments, glue orother adhesive is used on the laminate hammock 2406 to ensure the bucklearms 2404 stay in a position relative to a lens carriage.

FIG. 28 illustrates a laminate formed crimp connection of an SMAactuator according to an embodiment. The laminate formed crimpconnection 2412 is configured to attach an SMA wire 2408 to the buckleactuator and to create an electrical circuit joint with the SMA wire2408. For various embodiments, the laminated formed crimp connection2412 includes a laminate formed of one or more layers of an insulatorand one or more layers of a conductive layer formed on a crimp.

For example, a polyimide layer is disposed on at least a portion of thestainless steel portion forming a crimp 2413. A conductive layer, suchas copper, is then disposed on the polyimide layer, which iselectrically coupled with one or more signal traces 2415 disposed on thebuckle actuator. Deforming the crimp to come in to contact with the SMAwire therein also puts the SMA wire in electrical contact with theconductive layer. Thus, the conductive layer coupled with the one ormore signal traces is used to apply power signals to the SMA wire usingtechniques including those described herein. For some embodiments, asecond polyimide layer is formed over the conductive layer in areaswhere the conductive layer will not come into contact with the SMA wire.For some embodiments, the laminated formed crimp connection 2412 isformed on a crimp 2413 using deposition and etching techniques includingthose known in the art. For other embodiments, laminated formed crimpconnection 2412 and the one or more electrical traces are formedseparately from the crimp 2413 and the buckle actuator and attached tothe crimp 2413 and the buckle actuator using techniques includingwelding, adhesive, and other techniques known in the art.

FIG. 29 illustrates an SMA actuator including a buckle actuator with alaminate hammock. As illustrated in FIG. 29 , when a power signal isapplied the SMA wire contracts or shortens to move the buckle arms andthe laminate hammock in the positive z-direction. The laminate hammockthat is in contact with an object in turn moves that object, such as alens carriage in the positive z-direction. When the power signal isdecreased or removed the SMA wire lengthens and moving the buckle armsand the laminate hammock in a negative z-direction.

FIG. 30 illustrates an exploded view of an SMA system including an SMAactuator including a buckle actuator according to an embodiment. Asdescribed herein, SMA systems, for some embodiments, are configured tobe used in conjunction with one or more camera lens elements as anauto-focusing drive. As illustrated in FIG. 30 , the SMA system includesa return spring 3003 configured, according to various embodiments, tomove a lens carriage 3006 in the opposite direction of the z-strokedirection when the tension in the SMA wires 3008 is lowered as the SMAwire is de-actuated. The SMA system, for some embodiments, includes astiffner 3000 disposed on the return spring 3003. The SMA system forsome embodiments includes a housing 3009 formed of two portionsconfigured to receive the return spring 3003 and to act a slide bearingto guide the lens carriage in the z-stroke direction. The housing 3009is also configured to be disposed on the buckle actuator 3002. Thebuckle actuator 3002 includes a slide base 3001 similar to thosedescribed herein is formed of two portions. The slide base 3001 is splitto electrically isolate the 2 sides (for example 1 side is ground, otherside is power) because, according to some embodiments, current flows tothe wire through the slide base 3001 portions.

The buckle actuator 3002 includes buckle arms 3004. Each pair of buckleactuators 3002 are formed on a separate portion of the buckle actuator3002. The buckle actuator 3002 also includes a SMA wire attachstructures such as a resistance weld wire crimp 3012. The SMA systemoptionally includes a flex circuit 3020 for electrically coupling theSMA wires 3008 to one or more control circuits.

As illustrated in FIG. 30 , the slide base 3001 is disposed on anoptional adaptor plate 3014. The adaptor plate is configured to mate theSMA system or the buckle actuator 3002 to another system, such as anOIS, additional SMA systems, or other components. FIG. 31 illustrates anSMA system 3101 including an SMA actuator including a buckle actuator3002 according to an embodiment.

FIG. 32 includes an SMA actuator including a buckle actuator accordingto an embodiment. The buckle actuator 3002 includes buckle arms 3004.The buckle arms 3004 are configured to move in the z-axis when the SMAwires 3008 are actuated and de-actuated as described herein. The SMAwires 3008 are attached to the resistance weld wire crimps 3012.According to the embodiment illustrated in FIG. 32 , the buckle arms3004 are configured to mate with an object, such as a lens carriage,without a center portion using a two yoke capture joint.

FIG. 33 illustrates a two yoke capture joint of a pair of buckle arms ofan SMA actuator according to an embodiment. FIG. 33 also illustratesplating pads 3022 used to attached the optional flex circuit to thesliding base. For some embodiments, the plating pads 3022 are formedusing gold. FIG. 34 illustrates a resistance weld crimp for an SMAactuator according to an embodiment used to attach an SMA wire to thebuckle actuator. For some embodiments, glue or adhesive can also beplaced on top of the weld to aid in mechanical strength and work as afatigue strain relief during operation and shock loading.

FIG. 35 illustrates an SMA actuator including a buckle actuator with atwo yoke capture joint. As illustrated in FIG. 35 , when a power signalis applied the SMA wire contracts or shortens to move the buckle arms inthe positive z-direction. The two yoke capture joint is in contact withan object in turn moves that object, such as a lens carriage in thepositive z-direction. When the power signal is decreased or removed theSMA wire lengthens and moving the buckle arms in a negative z-direction.The yoke capture feature ensures buckle arms stay in correct positionrelative to the lens carriage.

FIG. 36 illustrates a SMA bimorph liquid lens according to anembodiment. The SMA bimorph liquid lens 3501 includes a liquid lenssubassembly 3502, a housing 3504, and a circuit with SMA actuators 3506.For various embodiments, the SMA actuators include 4 bimorph actuators3508, such as embodiments described herein. The bimorph actuators 3508are configured to push on a shaping ring 3510 located on a flexiblemembrane 3512. The ring warps the membrane 3512/liquid 3514 changing thelight path through the membrane 3512/liquid 3514. A liquid contain ring3516 is used to contain the liquid 3514 between the membrane 3512 andthe lens 3518. Equal force from Bimorph actuators changes the focuspoint of the image in the Z direction (normal to lens) which allows itto work as an auto focus. Differential force from Bimorph actuators 3508can move light rays in the X,Y axes directions which allows it to workas an optical image stabilizer according to some embodiments. Both OISand AF functions could be achieved at the same time with proper controlsto each actuator. For some embodiments, 3 actuators are used. Thecircuit with SMA actuators 3506 includes one or more contacts 3520 forcontrol signals to actuate the SMA actuators. According to someembodiments including 4 SMA actuators the circuit with SMA actuators3506 includes 4 power circuit control contact for each SMA actuator anda common return contact.

FIG. 37 illustrates a perspective SMA bimorph liquid lens according toan embodiment. FIG. 38 illustrates a cross-section and a bottom view ofSMA bimorph liquid lens according to an embodiment.

FIG. 39 illustrates an SMA system including an SMA actuator 3902 withbimorph actuators according to an embodiment. The SMA actuator 3902includes 4 bimorph actuators using techniques described herein. Two ofthe bimorph actuators are configured as positive z-stroke actuators 3904and two are configured as negative z-stroke actuators 3906 asillustrated in FIG. 40 , which illustrates the SMA actuator 3902 withbimorph actuators according to an embodiment. The opposing actuators3906, 3904 are configured to control motion in both directions over theentire stroke range. This provides the ability to tune control code tocompensate for tilt. For various embodiments, two SMA wires 3908attached to top of component enable the positive z-stroke displacement.Two SMA wires attached to a bottom of component enable the negativez-stroke displacement. For some embodiments, each bimorph actuators areattached to an object, such as a lens carriage 3910, using tabs toengage the object. The SMA system includes a top spring 3912 configuredto provide stability of the lens carriage 3910 in axes perpendicular tothe z-stroke axis, for example in the direction of the x axis and the yaxis. Further, a top spacer 3914 is configured to be arranged betweenthe top spring 3912 and the SMA actuator 3902. A bottom spacer 3916 isarranged between the SMA actuator 3902 and a bottom spring 3918. Thebottom spring 3918 is configured to provide stability of the lenscarriage 3910 in axes perpendicular to the z-stroke axis, for example inthe direction of the x axis and the y axis. The bottom spring 3918 isconfigured to be disposed on a base 3920, such as those describedherein.

FIG. 41 illustrates the length 4102 of a bimorph actuator 4103 and thelocation of a bonding pad 4104 for an SMA wire 4106 to extend the wirelength beyond the bimorph actuator. Longer wire than bimorph actuator isused to increased stroke & force. Thus, the extension length 4108 ofthat the SMA wire 4106 beyond the bimorph actuator 4103 is used to setthe stroke and force for the bimorph actuator 4103.

FIG. 42 illustrates an exploded view of an SMA system including a SMAbimorph actuator 4202 according to an embodiment. The SMA system,according to various embodiments, is configured to use separate metalmaterials and non-conductive adhesives to create one or more electricalcircuits to power the SMA wires independently. Some embodiments have noAF size impact and include 4 bimorph actuators, such as those describedherein. Two of the bimorph actuators are configured as positive z strokeactuators and two negative z stroke actuators. FIG. 43 illustrates anexploded view of a subsection of the SMA actuator according to anembodiment. The subsection includes a negative actuator signalconnection 4302, a base 4304 with bimorph actuators 4306. The negativeactuator signal connection 4302 includes a wire bond pad 4308 forconnecting an SMA wire of a bimorph actuator 4306 using techniquesincluding those described herein. The negative actuator signalconnection 4302 is affixed to the base 4304 using an adhesive layer4310. The subsection also includes a positive actuator signal connection4314 with a wire bond pad 4316 for connecting an SMA wire 4312 of abimorph actuator 4306 using techniques including those described herein.The positive actuator signal connection 4314 is affixed to the base 4304using an adhesive layer 4318. Each of the base 4304, the negativeactuator signal connection 4302, and the positive actuator signalconnection 4314 are formed of metal, for example stainless steel.Connection pads 4322 on each of the base 4304, the negative actuatorsignal connection 4302, and the positive actuator signal connection 4314are configured to electrically couple control signals and ground foractuating the bimorph actuator 4306 using techniques including thosedescribed herein. For some embodiments, the connection pads 4322 aregold plated. FIG. 44 illustrates a subsection of the SMA actuatoraccording to an embodiment. For some embodiments, gold platted pads areformed on the stainless steel layer for solder bonding or other knownelectrical termination methods. Further, formed wire bond pads are usedfor signal joints to electrically couple the SMA wires for powersignals.

FIG. 45 illustrates a 5 axis sensor shift system according to anembodiment. The 5 axis sensor shift system is configured to move anobject, such as an image sensor in 5 axis relative to one or more lens.This includes X/Y/Z axis translation and pitch/roll tilt. Optionally thesystem is configured to use only 4 axis with X/Y axis translation andpitch/roll tilt together with a separate AF on top to do Z motion. Otherembodiments include the 5 axis sensor shift system configured to moveone or more lens relative to an image sensor. Static lens stack mountedon top cover and inserts inside the ID (not touching the orange movingcarriage inside) for some embodiments.

FIG. 46 illustrates an exploded view of a 5 axis sensor shift systemaccording to an embodiment. The 5 axis sensor shift system includes 2circuit components: a flexible sensor circuit 4602, bimorph actuatorcircuit 4604; and 8-12 bimorph actuators 4606 built on to the bimorphcircuit component using techniques including those described herein. The5 axis sensor shift system includes a moving carriage 4608 configured tohold one or more lenses and an outer housing 4610. The bimorph actuatorcircuit 4604 includes, according to an embodiment, 8-12 SMA actuatorssuch as those described herein. The SMA actuators are configured to movethe moving carriage 4608 in 5 axis, such as in an x-direction, ay-direction, a z-direction, pitch, and roll similar to other 5 axissystems described herein.

FIG. 47 illustrates an SMA actuator including bimorph actuatorsintegrated into this circuit for all motion according to an embodiment.Embodiment of a SMA actuator can including 8-12 bimorph actuators 4606.However, other embodiments could include more or less. FIG. 48illustrates an SMA actuator 4802 including bimorph actuators integratedinto this circuit for all motion according to an embodiment partiallyformed to fit inside a corresponding outer housing 4804. FIG. 49illustrates a cross section of a 5 axis sensor shift system according toan embodiment.

FIG. 50 illustrates an SMA actuator 5002 according to an embodimentincluding bimorph actuators. The SMA actuator 5002 is configured to use4 side mounted SMA bimorph actuators 5004 to move an image sensor, lens,or other various payloads in the x and y direction. FIG. 51 illustratesa top view of an SMA actuator including bimorph actuators that moved animage sensor, lens, or other various payloads in different x and ypositions.

FIG. 52 illustrates an SMA actuator including bimorph actuators 5202according to an embodiment configured as a box bimorph autofocus. Fourtop and bottom mounted SMA bimorph actuators, such as those describedherein, are configured to move together to create movement in thez-stroke direction for autofocus motion. FIG. 53 illustrates an SMAactuator including bimorph actuators according to an embodiment andwhich two top mounted bimorph actuators 5302 are configured to push downon one or more lens. FIG. 54 illustrates an SMA actuator includingbimorph actuators according to an embodiment and which two bottommounted bimorph actuators 5402 are configured to push up on one or morelens. FIG. 55 illustrates an SMA actuator including bimorph actuatorsaccording to an embodiment to show the four top and bottom mounted SMAbimorph actuators 5502, such as those described herein, are used to movethe one or more lens to create tilt motion.

FIG. 56 illustrates a SMA system including a SMA actuator according toan embodiment including bimorph actuators configured as a two axis lensshift OIS. For some embodiments, the two axis lens shift OIS isconfigured to move a lens in the X/Y axis. For some embodiments, Z axismovement comes from a separate AF, such as those described herein. 4bimorph actuators push on sides of auto focus for OIS motion. FIG. 57illustrates an exploded view of SMA system including a SMA actuator 5802according to an embodiment including bimorph actuators 5806 configuredas a two axis lens shift OIS. FIG. 58 illustrates a cross-section of SMAsystem including a SMA actuator 5802 according to an embodimentincluding bimorph actuators 5806 configured as a two axis lens shiftOIS. FIG. 59 illustrates box bimorph actuator 5802 according to anembodiment for use in a SMA system configured as a two axis lens shiftOIS as manufactured before it is shaped to fit in the system. Such asystem can be configured to have high OIS stroke OIS (e.g., +/−200 μm ormore). Further, such embodiments are configured to have a broad range ofmotion and good OIS dynamic tilt using 4 slide bearings, such as POMslide bearings. The embodiments are configured to integrate easily withAF designs (e.g., VCM or SMA).

FIG. 60 illustrates a SMA system including a SMA actuator according toan embodiment including bimorph actuators configured as a five axis lensshift OIS and autofocus. For some embodiments, the five axis lens shiftOIS and autofocus is configured to move a lens in the X/Y/Z axis. Forsome embodiments, pitch and yaw axis motion are for dynamic tilt tuningcapability. 8 bimorph actuators are used to provide the motion for theauto focus and OIS using techniques described herein. FIG. 61illustrates an exploded view of SMA system including a SMA actuator 6202according to an embodiment including bimorph actuators 6204 according toan embodiment configured as a five axis lens shift OIS and autofocus.FIG. 62 illustrates a cross-section of SMA system including a SMAactuator 6202 according to an embodiment including bimorph actuators6204 configured as a five axis lens shift OIS and autofocus. FIG. 63illustrates box bimorph actuator 6202 according to an embodiment for usein a SMA system configured as a five axis lens shift OIS and autofocusas manufactured before it is shaped to fit in the system. Such a systemcan be configured to have high OIS stroke OIS (e.g., +/−200 μm or more)and a high autofocus stroke (e.g., 400 μm or more). Further, suchembodiments enable to tune out any tilt and remove the need for aseparate autofocus assembly.

FIG. 64 illustrates a SMA system including a SMA actuator according toan embodiment including bimorph actuators configured as an outwardpushing box. For some embodiments, the bimorph actuators assembly isconfigured to wrap around an object, such as a lens carriage. Since thecircuit assembly is moving with the lens carriage, a flexible portion isconfigured for low X/Y/Z stiffness. Tail pads of the circuit are static.The outward pushing box can be configured for both 4 or 8 bimorphactuators. So, the outward pushing box can be configured as a 4 bimorphactuator on the sides for OIS with movement in X and Y axis. The outwardpushing box can be configured as a 4 bimorph actuator on the top andbottom for autofocus with movement in z axis. The outward pushing boxcan be configured as an 8 bimorph actuator on the top, bottom, and sidesfor OIS and autofocus with movement in x, y, and z axis and capable of3-axis tilt (pitch/roll/yaw). FIG. 65 illustrates an exploded view of aSMA system including a SMA actuator 6602 according to an embodimentincluding bimorph actuators 6604 configured as an outward pushing box.Thus, the SMA actuator is configured such that the bimorph actuators acton the outer housing 6504 to move the lens carriage 6506 usingtechniques described herein. FIG. 66 illustrates a SMA system includinga SMA actuator 6602 according to an embodiment including bimorphactuators configured as an outward pushing box partially shaped toreceive a lens carriage 6603. FIG. 67 illustrates a SMA system includinga SMA actuator 6602 including bimorph actuators 6604 according to anembodiment configured as an outward pushing box as manufactured beforeit is shaped to fit in the system.

FIG. 68 illustrates a SMA system including a SMA actuator 6802 accordingto an embodiment including bimorph actuators 6806 configured as a threeaxis sensor shift OIS. For some embodiments, z axis movement comes froma separate autofocus system. 4 bimorph actuators configured to push onsides of a sensor carriage 6804 to provide the motion for the OIS usingtechniques described herein. FIG. 69 illustrates an exploded view of SMAincluding a SMA actuator 6802 according to an embodiment includingbimorph actuators 6806 configured as a three axis sensor shift OIS. FIG.70 illustrates a cross-section of SMA system including a SMA actuator6802 according to an embodiment including bimorph actuators 6806configured as a three axis sensor shift OIS. FIG. 71 illustrates a boxbimorph actuator 6802 component according to an embodiment for use in aSMA system configured as a three axis sensor shift OIS as manufacturedbefore it is shaped to fit in the system. FIG. 72 illustrates a flexiblesensor circuit for use in a SMA system according to an embodimentconfigured as a three axis sensor shift OIS. Such a system can beconfigured to have high OIS stroke OIS (e.g., +/−200 μm or more) and ahigh autofocus stroke (e.g., 400 μm or more). Further, such embodimentsare configured to have a broad range of two axis motion and good OISdynamic tilt using 4 slide bearings, such as POM slide bearings. Theembodiments are configured to integrate easily with AF designs (e.g.,VCM or SMA).

FIG. 73 illustrates a SMA system including a SMA actuator according toan embodiment including bimorph actuators 7404 configured as a six axissensor shift OIS and autofocus. For some embodiments, the six axissensor shift OIS and autofocus is configured to move a lens in theX/Y/Z/Pitch/Yaw/Roll axis. For some embodiments, pitch and yaw axismotion are for dynamic tilt tuning capability. 8 bimorph actuators areused to provide the motion for the auto focus and OIS using techniquesdescribed herein. FIG. 74 illustrates an exploded view of SMA systemincluding a SMA actuator 7402 according to an embodiment includingbimorph actuators 7404 configured as a six axis sensor shift OIS andautofocus. FIG. 75 illustrates a cross-section of SMA system including aSMA actuator 7402 according to an embodiment including bimorph actuatorsconfigured as a six axis sensor shift OIS and autofocus. FIG. 76illustrates box bimorph actuator 7402 according to an embodiment for usein a SMA system configured as a six axis sensor shift OIS and autofocusas manufactured before it is shaped to fit in the system. FIG. 77illustrates a flexible sensor circuit for use in a SMA system accordingto an embodiment configured as a three axis sensor shift OIS. Such asystem can be configured to have high OIS stroke OIS (e.g., +/−200 um ormore) and a high autofocus stroke (e.g., 400 μm or more). Further, suchembodiments enable to tune out any tilt and remove the need for aseparate autofocus assembly.

FIG. 78 illustrates a SMA system including a SMA actuator according toan embodiment including bimorph actuators configured as a two axiscamera tilt OIS. For some embodiments, the two axis camera tilt OIS isconfigured to move a camera in the Pitch/Yaw axis. 4 bimorph actuatorsare used to push on top and bottom of autofocus for entire camera motionfor the OIS pitch and yaw motion using techniques described herein. FIG.79 illustrates an exploded view of SMA system including a SMA actuator7902 according to an embodiment including bimorph actuators 7904configured as two axis camera tilt OIS. FIG. 80 illustrates across-section of SMA system including a SMA actuator according to anembodiment including bimorph actuators configured as a two axis cameratilt OIS. FIG. 81 illustrates box bimorph actuator according to anembodiment for use in a SMA system configured as a two axis camera tiltOIS as manufactured before it is shaped to fit in the system. FIG. 82illustrates a flexible sensor circuit for use in a SMA system accordingto an embodiment configured as a two axis camera tilt OIS. Such a systemcan be configured to have high OIS stroke OIS (e.g., plus/minus 3degrees or more). The embodiments are configured to integrate easilywith autofocus (“AF”) designs (e.g., VCM or SMA).

FIG. 83 illustrates a SMA system including a SMA actuator according toan embodiment including bimorph actuators configured as a three axiscamera tilt OIS. For some embodiments, the three axis camera tilt OIS isconfigured to move a camera in the Pitch/Yaw/Roll axis. 4 bimorphactuators are used to push on top and bottom of autofocus for entirecamera motion for the OIS pitch and yaw motion using techniquesdescribed herein and 4 bimorph actuators are used to push on sides ofautofocus for entire camera motion for the OIS roll motion usingtechniques described herein. FIG. 84 illustrates an exploded view of SMAsystem including a SMA actuator 8402 according to an embodimentincluding bimorph actuators 8404 configured as three axis camera tiltOIS. FIG. 85 illustrates a cross-section of SMA system including a SMAactuator according to an embodiment including bimorph actuatorsconfigured as a three axis camera tilt OIS. FIG. 86 illustrates boxbimorph actuator for use in a SMA system according to an embodimentconfigured as a three axis camera tilt OIS as manufactured before it isshaped to fit in the system. FIG. 87 illustrates a flexible sensorcircuit for use in a SMA system according to an embodiment configured asa three axis camera tilt OIS. Such a system can be configured to havehigh OIS stroke OIS (e.g., plus/minus 3 degrees or more). Theembodiments are configured to integrate easily with AF designs (e.g.,VCM or SMA).

FIG. 88 illustrates exemplary dimensions for a bimorph actuator of anSMA actuator according to embodiments. The dimensions are preferredembodiments but one skilled in the art would understand that otherdimensions could be used based on desired characteristics for an SMAactuator.

FIG. 89 illustrates a lens system for a folded camera according to anembodiment. The folded camera includes a folding lens 8902 configured tobend light to a lens system 8901 including one or more lens 8903 a-d.For some embodiments, the folding lens is one or more of any of a prismand lens. The lens system 8901 is configured to have a principal axis8904 that is at an angel to a transmission axis 8906 that is parallel tothe direction of travel of the light prior to the light reaching thefolding lens 8902. For example, a folded camera is used in a cameraphone system to reduce the height of a lens system 8901 in the directionof a transmission axis 8906.

Embodiments of the lens system include one or more liquid lens, such asthose described herein. The embodiment illustrated in FIG. 89 includestwo liquid lenses 8903 b,d, such as those described herein. The one ormore liquid lens 8903 b,d are configured to be actuated using techniquesincluding those describe herein. A liquid lens is actuated usingactuators, including but not limited to, buckle actuators, bimorphactuators, and other SMA actuators. FIG. 108 illustrates a liquid lensactuated using buckle actuators 60 according to an embodiment. Theliquid lens includes a shaping ring coupler 64, a liquid lens assembly61, one or more buckle actuators 60, such as those described herein, aslide base 65, and a base 62. The one or more buckle actuators 60 areconfigured to move the shaping ring/coupler 64 to change the shape of aflexible membrane of the liquid lens assembly 61 to move or shape thelight rays, for example as described herein. For some embodiments, 3 or4 actuators are used. A liquid lens can be configured alone or incombination with other lenses to act as an auto focus or optical imagestabilizer. A liquid lens can also be configured to otherwise direct animage onto an image sensor.

FIG. 90 illustrates several embodiments of a lens system 9001 includingliquid lenses 9002 a-h to focus an image on an image sensor 9004. Asillustrated, the liquid lens 9002 a-h may include any lens shape and beconfigured to be dynamically configured to adjust the light path throughthe lens using techniques including those describe herein.

A lens system for a folded camera is configured to include an actuatedfolding lens 9100. An example of an actuated folding lens is a prismtilt, such as that illustrated in FIG. 91 . In the example illustratedin FIG. 91 , the folding lens is a prism 9102 disposed on an actuator9104. The actuator includes, but is not limited to, an SMA actuatorincluding those described herein. For some embodiments, the prism tiltis disposed on an SMA actuator including 4 bimorph actuators 9106, suchas those described herein. The actuated folding lens 9100, according tosome embodiments, is configured as an optical image stabilizer usingtechniques including those described herein. For example, an actuatedfolding lens is configured to include an SMA system such as thatillustrated in FIG. 39 . Another example of an actuated folding lens caninclude an SMA actuator such as that illustrated in FIG. 21 . However,the folding lens may also include other actuators.

FIG. 92 illustrates a bimorph arm with an offset according to anembodiment. The bimorph arm 9201 includes a bimorph beam 9202 having alength 9208 and a formed offset 9203. The formed offset 9203 increasesthe mechanical advantage to generate a higher force than a bimorph armwithout an offset. According to some embodiments, the depth of theoffset 9204 (also referred herein as bend plane z offset 9204) and thelength of the offset 9206 (also referred herein as trough width 9206)are configured to define characteristics of the bimorph arm, such as thepeak force. For example, the graph in FIG. 106 illustrates therelationship between the bend plane z offset 9204, the trough width9206, and the peak force of a bimorph beam 9202 according to anembodiment.

The bimorph arm includes one or more SMA materials such as an SMA ribbonor SMA wire 9210, such as those described herein. The SMA material isaffixed to the beam using techniques including those describe herein.For some embodiments, the SMA material, such as an SMA wire 9210, isaffixed to a fixed end 9212 of the bimorph arm and to a load point end9214 of the bimorph arm so that the formed offset 9203 is between bothends where the SMA material is affixed. Ends of the SMA material, forvarious embodiments, are electrically and mechanically coupled withcontacts configured to supply current to the SMA material usingtechniques including those known in the art. The bimorph arm with anoffset can be included in SMA actuators and systems such as thosedescribed herein.

FIG. 93 illustrates a bimorph arm with an offset and a limiter accordingto an embodiment. The bimorph arm 9301 includes a bimorph beam 9302having a formed offset 9303 and a limiter 9304 adjacent to the formedoffset 9303. The offset 9303 increases the mechanical advantage togenerate a higher force than a bimorph arm 9301 without an offset andthe limiter 9304 prevents motion of the arm in direction away from theunfixed, load point end 9306 of the bimorph actuator. The bimorph arm9301 with a formed offset 9303 and limiter 9304 can be included in SMAactuators and systems such as those described herein. The bimorph arm9301 includes one or more SMA materials such as an SMA ribbon or SMAwire 9308, such as those described herein affixed to the bimorph arm9301 using techniques including those described herein.

FIG. 94 illustrates a bimorph arm with an offset and a limiter accordingto an embodiment. The bimorph arm 9401 includes a bimorph beam 9402having a formed offset 9403 and a limiter 9404 adjacent to the formedoffset 9403. The limiter 9404 is formed as part of a base 9406 for thebimorph arm 9401. The base 9406 is configured to receive a bimorph arm9401 and includes a recess 9408 configured to receive the offset portionof the bimorph beam. The bottom of the recess configured as a limiter9404 to be adjacent to the formed offset 9403. The base 9406 may alsoinclude one or more portions 9410 configured to support portions of thebimorph arm when it is not actuated. The bimorph arm 9401 with a formedoffset 9403 and limiter 9404 can be included in SMA actuators andsystems such as those described herein. The bimorph arm 9401 includesone or more SMA materials such as an SMA ribbon or SMA wire, such asthose described herein affixed to the bimorph arm 9401 using techniquesincluding those described herein.

FIG. 95 illustrates an embodiment of a base including a bimorph arm withan offset according to an embodiment. The bimorph arm 9501 includes abimorph beam 9502 having a formed offset 9504. The bimorph arm couldalso include a limiter using techniques including those describedherein. The bimorph arm 9501 includes one or more SMA materials such asan SMA ribbon or SMA wire 9506, such as those described herein affixedto the bimorph arm 9501 using techniques including those describedherein.

FIG. 96 illustrates an embodiment of a base 9608 including two bimorpharms with an offset according to an embodiment. Each bimorph arm 9601a,b includes a bimorph beam 9602 a,b having a formed offset 9604 a,b.Each bimorph arm 9601 a,b includes one or more SMA materials such as anSMA ribbon or SMA wire 9606 a,b, such as those described herein affixedto the bimorph arm 9501 using techniques including those describedherein. Each bimorph arm 9601 a,b could also include a limiter usingtechniques including those described herein. Some embodiments include abase including more than two bimorph arms formed using techniquesincluding those described herein. According to some embodiments, thebimorph arms 9601 are integrally formed with the base 9608. For otherembodiments, one or more of the bimorph arms 9601 a,b formed separatelyfrom the base 9608 and affixed to the base 9608, using techniquesincluding, but not limited to, solder, resistance welding, laserwelding, and adhesive. For some embodiments, two or more bimorph arms9601 a,b are configured to act on a single object. This enables theability to increase the force applied to an object. The following graphin FIG. 107 illustrates examples of how a box volume which is anapproximation of a box that encompasses the entire bimorph actuator isrelated to the work per bimorph component. The box volume isapproximated using a length of the bimorph actuator 9612, a width of thebimorph actuator 9610, and height of bimorph actuator 9614 (referredcollectively as “Box Volume”).

FIG. 97 illustrates a buckler arm including load point extensionsaccording to an embodiment. The buckler arm 9701 includes a beam portion9702 and one or more load point extensions 9704 a,b extending from thebeam portion 9702. Each end 9706 a,b of the buckler arm 9701 isconfigured to be affixed to or integrally formed to a plate or otherbase using techniques including those described herein. The one or moreload point extensions 9704 a,b, according to some embodiments, areaffixed or integrally formed with the beam portion 9702 at an offsetfrom a load point 9710 a,b of the beam portion 9702. The load point 9710a,b is the portion of the beam portion 9702 that is configured totransfer the force of the buckler arm 9701 to another object. For someembodiments, the load point 9710 a,b is the center of the beam portion9702. For other embodiments, the load point 9710 a,b is at a positionother than the center of the beam portion 9702. A load point extension9704 a,b is configured to extend from the point it is joined to the beamportion 9702 toward the load point 9710 a,b of the beam portion 9702 inthe direction of the longitudinal axis of the beam portion 9702. Forsome embodiments, the end of the load point extension 9704 a,b extendsto at least the load point 9710 a,b of the beam portion 9702. Thebuckler arm 9701 includes one or more SMA materials such as an SMAribbon or SMA wire 9712, such as those described herein. The SMAmaterial, such as an SMA wire 9712, is affixed at opposing ends of thebeam portion 9702. The SMA material is affixed to opposing ends of thebeam portion using techniques including those described herein. For someembodiments, the length of the load point extensions 9704 a,b can beconfigured to any length contained within the longitudinal length of theassociated flat (un-actuated) beam portion 9702 of the buckler arm 9701.

FIG. 98 illustrates a buckler arm 9801 including load point extensions9810 according to an embodiment in an actuated position. The SMAmaterial affixed to opposing ends of the beam portion 9802 is actuatedusing techniques including those described herein. The load point 9804enables the buckler arm 9801 to increase the stroke range over bucklerarms without the extensions. Thus, buckler arms including load pointextensions enable a greater maximum vertical stroke. The buckler armwith load point extensions can be included in SMA actuators and systemssuch as those described herein.

FIG. 99 illustrates a bimorph arm including load point extensionsaccording to an embodiment. The bimorph arm 9901 includes a beam portion9902 and one or more load point extensions 9904 a,b extending from thebeam portion. One end of the bimorph arm 9901 is configured to beaffixed to or integrally formed to a plate or other base usingtechniques including those described herein. The end of the beam portion9902 opposite the affixed or integrally formed end is not fixed and isfree to move. The one or more load point extensions 9904 a,b, accordingto some embodiments, are affixed or integrally formed with the beamportion 9902 at an offset from the free end of the beam portion 9902.The load point extension 9904 a,b is configured to extend from the pointit is joined to the beam portion 9902 in a direction away from a planeincluding the longitudinal axis of the beam portion 9902. For example,the one or more load point extensions 9904 a,b extend in the directionthat the free end of the beam portion extends when actuated. Someembodiments of a bimorph arm 9901 include one or more load pointextensions 9904 a,b having a longitudinal axis that forms an angleincluding 1 degree to 90 degrees with a plane including the longitudinalaxis of the beam portion. For some embodiments, the end 9910 a,b of theload point extension 9904 a,b is configured to engage an objectconfigured to be moved.

The bimorph arm 9901 includes one or more SMA materials such as an SMAribbon or SMA wire 9906, such as those described herein. The SMAmaterial, such as an SMA wire 9906, is affixed at opposing ends of thebeam portion 9902. The SMA material is affixed to opposing ends of thebeam portion 9902 using techniques including those described herein. Forsome embodiments, the length of the load point extensions 9904 a,b canbe configured to any length. The location of the point of engagement ofan object by an end 9910 a,b of the load point extension 9904 a,b,according to some embodiments, can be configured to be at any pointalong the longitudinal length of the beam portion 9902. The height abovethe beam portion of the end of a load point extension when the beamportion is flat (un-actuated) can be configured to be any height. Forsome embodiments, the load point extension can be configured to be atleast above other portions of the bimorph arm when the bimorph arm isactuated.

FIG. 100 illustrates a bimorph arm including load point extensionsaccording to an embodiment in an actuated position. The SMA materialaffixed to opposing ends of the beam portion 2 is actuated usingtechniques including those described herein. The load point extensions10 enable the bimorph arm 1 to increase the stroke force over bimorpharms without the extensions. Thus, bimorph arms 1 including load pointextensions 10 enable a greater force applied by the bimorph arm 1. Thebimorph arm 1 with load point extensions 10 can be included in SMAactuators and systems such as those described herein.

FIG. 101 illustrates an SMA optical image stabilizer according to anembodiment. The SMA optical image stabilizer 20 includes a moving plate22 and a static plate 24. The moving plate 22 includes spring arms 26integrally formed with the moving plate 22. For some embodiments, themoving plate 22 and the static plate 24 are each formed to be a unitary,one-piece plate. The moving plate 22 includes a first SMA materialattach portion 28 a and a second SMA material attach portion 28 b. Thestatic plate 24 includes a first SMA material attach portion 30 a and asecond SMA material attach portion 30 b. Each SMA material attachportion 28, 30 is configured to fix an SMA material, such as an SMAwire, to a plate using resistance weld joints. The first SMA materialattach portion 28 a of the moving plate 22 includes a first SMA wire 32a disposed between it and a first SMA material attach portion 30 a ofthe static plate and a second SMA wire 32 b disposed between it and thesecond SMA attach portion 30 b of the static plate 24. The second SMAmaterial attach portion 28 b of the moving plate 22 includes a third SMAwire 32 c disposed between it and a second SMA material attach portion30 b of the static plate and a fourth SMA wire 32 d disposed between itand the first SMA attach portion 30 a of the static plate 24. Actuatingeach SMA wire, using techniques including those described herein movethe moving plate 22 away from the static plate 24. FIG. 102 illustratesan SMA material attach portion 40 of a moving portion according to anembodiment. The SMA material attached portion is configured to have SMAmaterial, such as an SMA wire 41, resistance welded to the SMA materialattach portion 40. FIG. 103 illustrates an SMA attach portion 42 of astatic plate with resistance welded SMA wires 43 attached theretoaccording to an embodiment.

FIG. 104 illustrates an SMA actuator 45 including a buckle actuatoraccording to an embodiment. The buckle actuator 46 includes buckle arms47, such as those describe herein. The buckle arms 47 are configured tomove in the z-axis when the SMA wires 48 are actuated and de-actuatedusing techniques including those described herein. Each SMA wire 48 isattached to a respective resistance weld wire crimps 49 using resistancewelding. Each resistance weld wire crimp 49 includes an island 50isolated from the metal forming the buckle arms 47 on at least one sideof the SMA wire 48. The island structure can be used in other actuators,optical image stabilizer, and auto focus systems to connect at least oneside of an SMA wire to an isolated island structure formed in the basemetal layer, such as the OIS application shown in FIG. 101 .

FIG. 105 illustrates a resistance weld crimp including an island for anSMA actuator according to an embodiment used to attach an SMA wire 48 toa buckle actuator 46 using techniques including those describe here.FIG. 105 a illustrates a bottom portion of the SMA actuator 45. The SMAactuator 45, according to some embodiments, is formed from a stainlesssteel base layer 51. A dielectric layer 52, such as a polyimide layer,is disposed on the bottom portion of the stainless steel base layer 51.A conductor layer 53, according to some embodiments, is electricallyconnected to the stainless steel island 50 through a via in thedielectric layer 52 enabling an electrical connection to be made betweenthe wire welded to the stainless steel island 50 and the conductorcircuit attached to the stainless steel island. An island 50, accordingto some embodiments, is etch from the stainless steel base layer. Thedielectric layer 52 maintains the position of the island 50 within thestainless steel base layer 51. The island 50 is configured to attachedan SMA wire thereto using techniques including those described herein,such as resistance welding. FIG. 105 b illustrates a top portion of theSMA actuator 45 including an island 50. For some embodiments, glue oradhesive can also be placed on top of the weld to aid in mechanicalstrength and work as a fatigue strain relief during operation and shockloading.

FIG. 108 includes a lens system including an SMA actuator with buckleactuators according to an embodiment. The lens system includes a liquidlens assembly 61 disposed on a base 62. The lens system also includes ashaping ring/coupler 64 that is mechanically coupled with the buckleactuators 60. The SMA actuator including the buckle actuators 60, suchas those described herein, is disposed a slide base 65 which is disposedon the base 62. The SMA actuator is configured to move the shapingring/coupler 64 along the optical axis of the liquid lens assembly 61 byactuating the buckle actuators 60 using techniques including thosedescribed herein. This moves the shaping ring/coupler 64 to change thefocus of the liquid lens in the liquid lens assembly.

FIG. 109 illustrates an unfixed, load point end of a bimorph armaccording to an embodiment. The unfixed, load point end 70 of a bimorpharm includes a flat surface 71 to affix SMA material, such as an SMAwire 72. The SMA wire 72 is affixed to the flat surface 71 by aresistance weld 73. The resistance weld 73 is formed using techniquesincluding those known in the art.

FIG. 110 illustrates an unfixed, load point end of a bimorph armaccording to an embodiment. The unfixed, load point end 76 of a bimorpharm includes a flat surface 77 to affix SMA material, such as an SMAwire 78. The SMA wire 78 is affixed to the flat surface 77 by aresistance weld, similar to that illustrated in FIG. 109 . An adhesive79 is disposed on the resistance weld. This enables a more reliablejoint between the SMA wire 78 and the unfixed, load point end 76. Theadhesive 79 includes, but is not limited to, conductive adhesive,non-conductive adhesive, and other adhesives known in the art.

FIG. 111 illustrates an unfixed, load point end of a bimorph armaccording to an embodiment. The unfixed, load point end 80 of a bimorpharm includes a flat surface 81 to affix SMA material, such as an SMAwire 82. A metallic interlayer 84 is disposed on the flat surface 81.The metallic interlayer 84 includes, but is not limited to, a goldlayer, a nickel layer, or alloy layer. The SMA wire 82 is affixed to themetallic interlayer 84 disposed on the flat surface 81 by a resistanceweld 83. The resistance weld 83 is formed using techniques includingthose known in the art. The metallic interlayer 84 enables betteradhesion with the unfixed, load point end 80.

FIG. 112 illustrates an unfixed, load point end of a bimorph armaccording to an embodiment. The unfixed, load point end 88 of a bimorpharm includes a flat surface 89 to affix SMA material, such as an SMAwire 90. A metallic interlayer 92 is disposed on the flat surface 89.The metallic interlayer 92 includes, but is not limited to, a goldlayer, a nickel layer, or alloy layer. The SMA wire 90 is affixed to theflat surface 89 by a resistance weld, similar to that illustrated inFIG. 111 . An adhesive 91 is disposed on the resistance weld. Thisenables a more reliable joint between the SMA wire 90 and the unfixed,load point end 88. The adhesive 91 includes, but is not limited to,conductive adhesive, non-conductive adhesive, and other adhesives knownin the art.

FIG. 113 illustrates a fixed end of a bimorph arm according to anembodiment. The fixed end 95 of a bimorph arm includes a flat surface 96to affix SMA material, such as an SMA wire 97. The SMA wire 97 isaffixed to the flat surface 96 by a resistance weld 98. The resistanceweld 98 is formed using techniques including those known in the art.

FIG. 114 illustrates a fixed end of a bimorph arm according to anembodiment. The fixed end 120 of a bimorph arm includes a flat surface121 to affix SMA material, such as an SMA wire 122. The SMA wire 122 isaffixed to the flat surface 121 by a resistance weld, similar to thatillustrated in FIG. 113 . An adhesive 123 is disposed on the resistanceweld. This enables a more reliable joint between the SMA wire 122 andthe fixed end 120. The adhesive 123 includes, but is not limited to,conductive adhesive, non-conductive adhesive, and other adhesives knownin the art.

FIG. 115 illustrates a fixed end of a bimorph arm according to anembodiment. The fixed end 126 of a bimorph arm includes a flat surface127 to affix SMA material, such as an SMA wire 128. A metallicinterlayer 130 is disposed on the flat surface 127. The metallicinterlayer 130 includes, but is not limited to, a gold layer, a nickellayer, or alloy layer. The SMA wire 128 is affixed to the metallicinterlayer 130 disposed on the flat surface 127 by a resistance weld129. The resistance weld 129 is formed using techniques including thoseknown in the art. The metallic interlayer 130 enables better adhesionwith the fixed end 126.

FIG. 116 illustrates a fixed end of a bimorph arm according to anembodiment. The fixed end 135 of a bimorph arm includes a flat surface136 to affix SMA material, such as an SMA wire 137. A metallicinterlayer 138 is disposed on the flat surface 136. The metallicinterlayer 138 includes, but is not limited to, a gold layer, a nickellayer, or alloy layer. The SMA wire 137 is affixed to the flat surface136 by a resistance weld, similar to that illustrated in FIG. 115 . Anadhesive 139 is disposed on the resistance weld. This enables a morereliable joint between the SMA wire 137 and the fixed end 135. Theadhesive 139 includes, but is not limited to, conductive adhesive,non-conductive adhesive, and other adhesives known in the art.

FIG. 117 illustrates a backside view of a fixed end of a bimorph armaccording to an embodiment. The bimorph arm is configured according toembodiments described herein. The fixed end 143 of a bimorph armincludes an island 144 isolated from the outer portion 145 of the fixedend 143. This enabled the island 144 to be electrically and/or thermallyisolated from the outer portion 145. For some embodiments, SMA materialaffixed to the opposite side of the fixed end 143 of the bimorph arm iselectrically coupled with the SMA material, such as an SMA wire, througha via. The island 144 is disposed on an insulator 146, such as thosedescribed herein. The island 144 can be formed using etching techniquesincluding those known in the art.

FIG. 118 illustrates an unfixed, load point end 870 of a bimorph armaccording to an embodiment. The unfixed, load point end 870 of a bimorpharm includes a flat surface 871 configured to include radiant surfaceareas 874 extending out from the resistance weld region 873. The radiantsurface areas 874 include a distal portion 876 and a proximal portion875. The flat surface 871 is configured to have SMA material, such as anSMA wire 872, material affixed to the flat surface 871. According tosome embodiments, the SMA wire 872 is affixed to the flat surface 871 ata resistance weld region 873 by a resistance weld. The resistance weldis formed using techniques including those known in the art. For otherembodiments, the SMA wire 872 is affixed to the flat surface 871 usingother attachment techniques including those described herein.

A temperature reduction of the unfixed, load point end 870 is relativeto the phase transition temperature of the SMA wire 872. The radiantsurface area 874 increases the surface area of the unfixed load pointend 870 significantly.

The increased surface area improves the temperature reduction of theunfixed, load point end 870. The increased surface area enables coolingto prevent shape memory alloy phase transition during actuation.

FIG. 119 illustrates an unfixed, load point end 170 of a bimorph armaccording to an embodiment. The unfixed, load point end 170 of a bimorpharm includes a flat surface 171 configured to include radiant surfaceareas 174 extending out from the resistance weld region 173.

The radiant surface areas 174 include a distal portion 176 and aproximal portion 175. The flat surface 171 is configured to have SMAmaterial, such as an SMA wire 172, affixed to the flat surface 171.According to some embodiments, the SMA wire 172 is affixed to the flatsurface 171 by a resistance weld to a resistance weld region 173. Forother embodiments, the SMA wire 172 is affixed to the flat surface 171using other attachment techniques including those described herein.

The unfixed, load point end 170 also includes a proximal aperture 178and a distal aperture 179 separated by the resistance weld region 173.The proximal aperture 178 and distal aperture 179 is formed usingtechniques including those known in the art. While the apertures 178 and179 are illustrated as full through features, the apertures 178 and 179may be partially etched in some examples.

The proximal aperture 178 and a distal aperture 179 physically break theflat surface 171 and define the position of the resistance weld region173. The apertures 178 and 179, according to some embodiments, areconfigured to relieve interference between the wire 172 and flat surface171 near the resistance weld region 173.

FIG. 120 illustrates an unfixed, load point end 270 of a bimorph armaccording to an embodiment. The unfixed, load point end 270 of a bimorpharm includes a flat surface 271 configured to include radiant surfaceareas 274 extending out from the resistance weld region 273. The flatsurface 271 is configured to have SMA material, such as an SMA wire 272,affixed to the flat surface 271. According to some embodiments, the SMAwire 272 is affixed to the flat surface 271 by a resistance weld to aresistance weld region 273. For other embodiments, the SMA wire 272 isaffixed to the flat surface 271 using other attachment techniquesincluding those described herein.

The unfixed, load point end 270 also includes a proximal aperture 278and a distal aperture 279 separated by the resistance weld region 273.The unfixed, load point end 270 also includes an elongated aperture 280corresponding to a section of the SMA wire 272. The elongated aperture280 can be removed to create a wire clearance for the SMA wire 272. Insome embodiments, the elongated aperture 280 extends from the proximalaperture 278. While the apertures 278, 279, and 280 are illustrated asfull through features, the apertures 278, 279, and 280 may be partiallyetched in some examples.

The proximal aperture 278 and a distal aperture 279 physically break theflat surface 271 and define the position of the resistance weld region273. Similarly, the elongated aperture 280 physically break the flatsurface 271 and define the position of the SMA wire 272. The apertures278, 279, and 280, according to some embodiments, are configured torelieve interference between the wire 272 and the flat surface 271 nearthe resistance weld region 273.

FIG. 121 illustrates an unfixed, load point end 370 of a bimorph armaccording to an embodiment. The flat surface 371 is configured to haveSMA material, such as an SMA wire 372, affixed to the flat surface 371.According to some embodiments, the SMA wire 372 is affixed to the flatsurface 371 by a resistance weld to a resistance weld region 373, whichis isolated, at least in part, by a non-linear aperture 378. In someconfigurations, the non-linear aperture 378 is u-shaped, to physicallyisolate up to 90% of the resistance weld region 373. The resistance weldregion 373 could be mounted on a weld tongue defined by the non-linearaperture 378. For other embodiments, the SMA wire 372 is affixed to theflat surface 371 using other attachment techniques including thosedescribed herein. While the non-linear aperture 378 is illustrated as afull through feature, the non-linear aperture 378 may be partiallyetched in some examples.

The increased surface area from the radiant surface areas 374 enablescooling to prevent shape memory alloy phase transition during actuation.In some alternative embodiments, the resistance weld region 373 may befully etched from the unfixed, load point end 370. Alternatively, theresistance weld region 373 could also contain a partial etch slot toincrease the compliance of the tongue.

FIG. 122 illustrates an unfixed, load point end 470 of a bimorph armaccording to an embodiment. The adjacent flat surfaces 471 are providedto affix SMA material, such as an SMA wire 472. The SMA wire 472 isaffixed to the flat surface 471 by a resistance weld region 473, whichis isolated, at least in part, by a non-linear aperture 478.

The resistance weld region 473 could be mounted using a partial etchslot 479 in the non-linear aperture 478. In some configurations, thenon-linear aperture 478 physically breaks the flat surface 471 anddefine the position of the resistance weld region 473. The apertures 178and 179, according to some embodiments, are configured to relieveinterference between the wire 172 and flat surface 171 near theresistance weld region 173. While the apertures 178 and 179 areillustrated as full through features, the apertures 178 and 179 may bepartially etched in some examples.

The increased surface area from the radiant surface areas 474 enablecooling to prevent shape memory alloy phase transition during actuation.

The disclosed embodiments can be applied to fixed ends of the bimorpharm. FIGS. 123-125 are provided herein as example embodiments of fixedends incorporating the disclosed embodiments.

FIG. 123 illustrates a fixed end of a bimorph arm according to anembodiment. The fixed end 895 of a bimorph arm includes a flat surface896 to affix SMA material, such as an SMA wire 897. The SMA wire 897 isaffixed to the flat surface 896 by a resistance weld region 898. Theresistance weld region 898 is formed using techniques including thoseknown in the art.

The fixed end 895 includes a proximal aperture 893 and a distal aperture894 separated by the resistance weld region 898. The proximal aperture893 and distal aperture 894 are formed using techniques including thoseknown in the art.

The proximal aperture 893 and a distal aperture 894 physically breaksthe flat surface 896 and define the position of the resistance weld 898.The apertures 893 and 894, according to some embodiments, are configuredto relieve interference between the SMA wire 897 and the flat surface896 near the resistance weld region 898. While the apertures 893 and 894are illustrated as full through features, the apertures 893 and 894 maybe partially etched in some examples.

FIG. 124 illustrates a fixed end of a bimorph arm according to anembodiment. The fixed end 195 of a bimorph arm includes a flat surface196 to affix SMA material, such as an SMA wire 197. The SMA wire 197 isaffixed to the flat surface 196 by a resistance weld at a resistanceweld region 198. The resistance weld region 198 is formed usingtechniques including those known in the art.

The fixed end 195 includes a proximal aperture 193 and a distal aperture194 separated by the resistance weld region 198. The proximal aperture193 and distal aperture 194 are formed using techniques including thoseknown in the art.

The fixed end 195 also includes an elongated aperture 160 correspondingto a section of the SMA wire 197. The elongated aperture 160 can beremoved to provide a wire clearance for the SMA wire 197. In someembodiments, the elongated aperture 160 extends from the distal aperture194.

The proximal aperture 193 and a distal aperture 194 physically isolate,at least in part, the resistance weld region 198. The elongated aperture160 physically break the flat surface 196 and define the position of theSMA wire 197. The apertures 193 and 194, according to some embodiments,are configured to relieve interference between the SMA wire 197 and theflat surface 196 near the resistance weld region 198. While theapertures 193 and 194 are illustrated as full through features, theapertures 193 and 194 may be partially etched in some examples.

FIG. 125 illustrates a fixed end 295 of a bimorph arm according to anembodiment. The fixed end 295 of a bimorph arm includes a flat surface296 to affix SMA material, such as an SMA wire 297. The SMA wire 297 isaffixed to the flat surface 296 by a resistance weld at a resistanceweld region 298.

The resistance weld region 298 is isolated, at least in part, by anon-linear aperture 294. In some configurations, the non-linear aperture294 is u-shaped, to physically isolate up to 90% of the resistance weldregion 298. The resistance weld 298 could be mounted on a weld tonguedefined by the non-linear aperture 294.

The non-linear aperture 294 physically break the flat surface 296 anddefine the position of the resistance weld region 298. The linearaperture 294, according to some embodiments, is configured to relieveinterference between the SMA wire 297 and the flat surface 296 near theresistance weld region 298. In some alternative embodiments, theresistance weld region 298 may be fully etched from the fixed end 295.Alternatively, the resistance weld region 298 could also contain apartial etch slot to reduce a contact area.

FIG. 126 illustrates a balanced bimorph actuator according to anembodiment. The balanced bimorph actuator 440 includes two bimorph arms442, 443 formed and configured using techniques including thosedescribed herein. For some embodiments the bimorph actuator 440 is fixedto a base 441, such as a carriage for mounting to an outer housing. Thebimorph actuator 440 is fixed to the base using techniques includingthose known in the art, such as adhesive and solder. The balancedbimorph actuator 440 is configured to reduce the net friction force ofthe bimorph actuator 440 by minimizing or canceling out their ownfriction components 444 a,b since it include two bimorph arms 442, 443that are arranged in opposite directions. The friction force component444 a,b of each bimorph arm 442, 443 acts in a direction different fromthe wanted force stroke 445 a,b of each bimorph arm 442, 443. Accordingto some embodiments, a balanced bimorph actuator 440 includes at least afirst bimorph arm 442 and at least another bimorph arm 443 configured tohave a friction force component 444 a,b that acts in an oppositedirection of the first bimorph arm 442. Thus, the balanced bimorphactuator 440 is configured to balance the sliding friction caused by oneor more bimorph arms because of friction force components. This enablesmore accurate control with less or no need to actively counteractunwanted friction forces. The balanced bimorph actuator including thosedescribed herein overcome problems of other bimorph actuators thatcreate a frictional force component at the tip. These other bimorphactuators create a push in the a Y direction and also create an unwantedforce in the X direction due to sliding along the surface of the pushedmember of the actuator in the X direction. This will create a smallamount of unwanted motion in the X direction that the control systemwill have to compensate for. However, these compensating bimorphactuators will also induce their own unwanted frictional forces. Thisrequires complex control algorithms to achieve good motion performance,for example as used in an optical image stabilization system.

FIG. 127 illustrates an optical image stabilization including balancedbimorph actuators according to an embodiment. The balanced bimorphactuators 448 a-d on all sides act to cancel out their own frictioncomponents since they are arranged in opposite directions usingtechniques including those described herein. With approximately net zerofriction there is minimal open loop position error. Small errors willbe, in some examples, due to typical assembly and component sizetolerances and can be easily corrected by using a closed loop controlsystem.

FIG. 128 illustrates a balanced bimorph actuator according to anembodiment. The balanced bimorph actuator 450 includes two bimorph arms452 a,b, such as those described herein, arranged in an inline, mirroredorientation. For some embodiments the bimorph actuator 450 is fixed to abase 453, such as a carriage for mounting to an outer housing. Thebimorph actuator 450 is fixed to the base using techniques includingthose known in the art, such as adhesive and solder. According to someembodiments, a first bimorph arm 452 a is configured to have a frictionforce component 454 a in primarily in the direction of the fixed end ofthe first bimorph arm 456 a parallel to a longitudinal axis of thebalanced bimorph actuator. The second bimorph arm 452 b is configuredinline with the first bimorph arm 452 a such that the fixed end of thesecond bimorph arm 456 b is adjacent to the fixed end of the firstbimorph arm 456 a. The second bimorph arm 452 b is configured to have afriction force component 454 b in a direction opposite to the firstbimorph arm 452 a. This results in bimorph actuator configured to reducethe net friction force of the bimorph actuator by minimizing orcanceling the net friction force. For some embodiments, the net frictionforce is approximately a net total friction of zero for the balancedbimorph actuator. For some embodiments, each bimorph arm 452 a,b of thebalanced bimorph actuator includes an SMA wire 458 a,b. The SMA wires458 a,b are connected in series and configured receive equal current toboth wires. For some embodiments, the first SMA wire 458 a is coupledwith a actuation control, for example through a 1-channel input tocontrol actuation of the actuator, through a first bimorph arm 452 acoupled with a control input pad 451 a. The second SMA wire 458 b iscoupled with ground through a second bimorph arm 452 b coupled with aground pad 451 b.

FIG. 129 illustrates a balanced bimorph actuator according to anembodiment including a polyimide layer 459 configured to hold andisolates metal components. Other embodiments of the balanced bimorphactuator do not include a polyimide layer. For some embodiments of thebalanced bimorph actuator without a polyimide layer, a control inputpad, a ground pad, and a common base island are fixed to a base layerbetween the fixed ends of the first bimorph arm and the second bimorpharm. For some embodiments the control input pad, the ground pad, and thecommon base island are fixed to a base layer using an adhesive, such asthose known in the art. FIG. 130 illustrates a balanced bimorph actuatoraccording to an embodiment including a common base island 460. Thecommon base island 460 is configured for attaching one end of a firstSMA wire and one end of a second SMA wire. For some embodiments, thecommon base island 460 is electrically isolated from a control input pad461 a and a ground pad 461 b before any SMA wires are affixed to thecommon base island 460. The common base island 460 is formed on thefixed end for a first bimorph arm 462 a and a second bimorph arm 462 b.

FIG. 131 illustrates a balanced bimorph actuator according to anembodiment. The balanced bimorph actuator includes two bimorph arms 464a,b, such as those described herein, arranged in an reversed inlineorientation. For some embodiments the bimorph actuator is fixed to abase 463, such as a carriage for mounting to an outer housing. Thebimorph actuator is fixed to the base using techniques including thoseknown in the art, such as adhesive and solder. According to someembodiments, a first bimorph arm 464 a is configured to have a frictionforce component 466 a in primarily in the direction of the fixed end 468a of the first bimorph arm 464 a parallel to a longitudinal axis of thebalanced bimorph actuator. The second bimorph arm 464 b is configuredinline with the first bimorph arm 464 a such that the fixed ends 468 a,bof the bimorph arms 464 a,b are at opposing ends of the bimorphactuator. Thus, the unfixed end of the first bimorph arm 469 a and theunfixed end of the second bimorph 469 b are arranged near each other.The second bimorph arm 464 b is configured to have a friction forcecomponent 466 b in a direction opposite to the first bimorph arm 464 a.This results in bimorph actuator configured to reduce the net frictionforce of the bimorph actuator by minimizing or canceling the netfriction force. For some embodiments, the net friction force isapproximately a net total friction of zero for the balanced bimorphactuator. For some embodiments, each bimorph arm 464 a,b of the balancedbimorph actuator includes an SMA wire 467 a,b. The SMA wires 467 a,b areconnected in series and configured receive equal current to both wires,for example through a 1-channel input to control actuation of theactuator. For some embodiments, the first SMA wire 467 a is coupled withan actuation control, for example through a 1-channel input to controlactuation of the actuator, through a first bimorph arm 452 a coupledwith a control input pad 451 a. The second SMA wire 458 b is coupledwith ground through a second bimorph arm 452 b coupled with a ground pad451 b.

FIG. 132 illustrates a balanced bimorph actuator according to anembodiment using techniques described herein including a polyimide layer570 configured to hold and isolate metal components. Other embodimentsof the balanced bimorph actuator do not include a polyimide layer. Forsome embodiments of the balanced bimorph actuator without a polyimidelayer, a control input pad and a ground pad are fixed adjacent to thefirst bimorph arm and the second bimorph arm. For some embodiments thecontrol input pad and a ground pad are fixed to a base layer using anadhesive, such as those known in the art. FIG. 133 illustrates abalanced bimorph actuator using techniques described herein according toan embodiment including a control input pad 572 and a ground pad 573.

FIG. 134 illustrates a balanced bimorph actuator according to anembodiment. The balanced bimorph actuator includes two bimorph arms 574a,b, such as those described herein, arranged in an inline, mirroredorientation. For some embodiments the bimorph actuator is fixed to abase 571, such as a carriage for mounting to an outer housing. Thebimorph actuator is fixed to the base using techniques including thoseknown in the art, such as adhesive and solder. According to someembodiments, a first bimorph arm 574 a is configured to have a frictionforce component 575 a primarily in the direction of the fixed end of thefirst bimorph arm 576 a parallel to a longitudinal axis of the balancedbimorph actuator. The second bimorph arm 574 b is configured inline withthe first bimorph arm 574 a such that the fixed end of the secondbimorph arm 576 b is adjacent to the fixed end of the first bimorph arm576 a. The second bimorph arm 574 b is configured to have a frictionforce component 575 b in a direction opposite to the friction forcecomponent of the first bimorph arm 575 a. This results in bimorphactuator configured to reduce the net friction force of the bimorphactuator by minimizing or canceling the net friction force. For someembodiments, the net friction force is approximately a net totalfriction of zero for the balanced bimorph actuator. For someembodiments, a single SMA wire 578 is used and each end of the SMA wire578 is coupled to a respective unfixed end of each bimorph arm 577 a,b.The single SMA wire 578 enables more stroke for the balanced bimorphactuator.

FIG. 135 illustrates a balanced bimorph actuator according to anembodiment using techniques described herein including a single SMA wire579. FIG. 136 illustrates a balanced bimorph actuator according to anembodiment using techniques described herein configured for a single SMAwire, and including a control input pad 480, and a ground pad 481. Forsome embodiments, the balanced bimorph actuator is configured to includea polyimide layer configured to hold and isolate metal components. Otherembodiments of the balanced bimorph actuator do not include a polyimidelayer. For some embodiments of the balanced bimorph actuator without apolyimide layer, a control input pad and a ground pad are fixed to abase layer between the fixed ends of the first bimorph arm and thesecond bimorph arm. For some embodiments the control input pad and aground pad are fixed to a base layer using an adhesive, such as thoseknown in the art.

FIG. 137 illustrates a balanced bimorph actuator according to anembodiment. The balanced bimorph actuator includes two bimorph arms 482a,b, such as those described herein, arranged in a staggeredorientation. For some embodiments the bimorph actuator is fixed to abase 489, such as a carriage for mounting to an outer housing. Thebimorph actuator is fixed to the base using techniques including thoseknown in the art, such as adhesive and solder. According to someembodiments, a first bimorph arm 482 a is configured to have a frictionforce component 483 a primarily in the direction of the fixed end of thefirst bimorph arm 484 a parallel to a longitudinal axis of the firstbimorph arm. The second bimorph arm 482 b is configured to be staggeredwith the first bimorph arm 482 a such longitudinal axis of the secondbimorph arm is approximately parallel to the longitudinal axis of thefirst bimorph arm. Further, the fixed ends of the bimorph arms 484 a,bare at opposing ends of the bimorph actuator. Thus, the unfixed end ofthe first bimorph arm 484 a and the unfixed end of the second bimorph484 b are staggered with respect to each other. The second bimorph arm482 a is configured to have a friction force component 483 a in adirection opposite to the first bimorph arm 482 a. This results inbimorph actuator configured to reduce the net friction force of thebimorph actuator by minimizing or canceling the net friction force. Forsome embodiments, the net friction force is approximately a net totalfriction of zero for the balanced bimorph actuator. For someembodiments, each bimorph arm 482 a,b of the balanced bimorph actuatorincludes an SMA wire 485 a,b. The SMA wires 485 a,b are connected inseries and configured receive equal current to both wires, for examplethrough a 1-channel input to control actuation of the actuator, such asthose described herein.

FIG. 138 illustrates a balanced bimorph actuator with a staggeredorientation according to an embodiment including a polyimide layer 486configured to hold and isolate metal components. Other embodiments ofthe balanced bimorph actuator do not include a polyimide layer. For someembodiments of the balanced bimorph actuator without a polyimide layer,a control input pad and a ground pad are fixed adjacent to the firstbimorph arm and the second bimorph arm. For some embodiments the controlinput pad and a ground pad are fixed to a base layer using an adhesive,such as those known in the art. FIG. 139 illustrates a balanced bimorphactuator according to an embodiment including a control input pad 487and a ground pad 488.

FIG. 140 illustrates an optical image stabilization system includingbalanced bimorph actuators according to an embodiment. The balancedbimorph actuators on all sides act to cancel out their own frictioncomponents since they are arranged in opposite directions. Withapproximately net zero friction there is minimal open loop positionerror. Small errors will be, in some examples, due to typical assemblyand component size tolerances and can be easily corrected by using aclosed loop control system.

FIG. 141 illustrates an exploded view of an optical image stabilizationsystem including balanced bimorph actuators according to an embodiment.The optical image stabilization is configured to receive bimorphactuators, such as those described herein, that self locates flush intoa pocket 510 a-d around the perimeter of the outer housing 511. Thisarrangement enables a smaller X/Y footprint of the bimorph module 512a-d by having bimorph actuators 514 a-d, such as the balanced bimorphactuators described herein, share the same X/Y space as the outerhousing 511. This also simplifies assembly of the bimorph module 512 a-dby enabling bimorph actuators 510 a-d to be inserted at the final stepfrom the outside. The outer housing 511 can be made from molded plastic,metal or other materials.

FIG. 142 illustrates an optical image stabilization system includingbalanced bimorph actuators according to an embodiment. The optical imagestabilization outer housing 516 is configured to receive bimorphactuators 518 a-d, such as those described herein, that self locatesflush into a pocket on the outer housing 516. This arrangement enables asmaller X/Y footprint of the bimorph module 520 a-d by having bimorphactuators 518 a-d, such as the balanced bimorph actuators describedherein, share the same X/Y space as the outer housing. This alsosimplifies assembly of the bimorph module 520 a-d by enabling bimorphactuators 518 a-d to be inserted at the final step from the outside. Theouter housing 516 can be made from molded plastic, metal or othermaterials.

FIG. 143 illustrates a sensor shift optical image stabilization systemincluding bimorph actuators according to an embodiment. The opticalimage stabilization system is configured to receive balanced bimorphactuators, such as those described herein, configured as a balancedcarriage/module 522 a-d. The bimorph carriage/module 522 a-d configuredto insert from the outside of the sensor shift OIS module. For someembodiments, the sensor shift OIS uses the design of the bimorphactuators off center to also induce rotation of the image sensor 524mounted on a moving image sensor carriage 528 which can be controlledfor suppressing roll excitation as well as X/Y excitation. Thisarrangement enables a smaller X/Y footprint of the bimorph module 522a-d by having bimorph actuators, such as the balanced bimorph actuatorsdescribed herein, share the same X/Y space as the outer housing 526.This also simplifies assembly of the bimorph module 522 a-d by enablingbimorph actuators to be inserted at the final step from the outside. Theouter housing 526 can be made from molded plastic, metal or othermaterials.

FIG. 144 illustrates an optical image stabilization system includingbalanced bimorph actuators according to an embodiment. The optical imagestabilization is configured to receive bimorph actuators, such as thosedescribed herein, that self locates flush into a pocket 530 on the outerhousing 532 of an optical image stabilization. This arrangement enablesa smaller X/Y footprint of the bimorph module 534 a-d by having bimorphactuators, such as the balanced bimorph actuators described herein,share the same X/Y space as the outer housing 532. This also simplifiesassembly of the bimorph module 534 a-d by enabling bimorph actuators tobe inserted at the final step from the outside. The outer housing 532can be made from molded plastic, metal or other materials.

FIG. 145 illustrates a metal outer housing 536 for an optical imagestabilization system, according to embodiments described herein,manufactured as formed metal that is attached with molded plastic 538a-d in an insert molding process. FIG. 146 illustrates a metal outercan/housing 536 embodiment including formed pockets 542 a-d into the 4sides of the metal outer can/housing 536 configured to allow for theflush mounting of bimorph actuators 544 a-d, such as those describedherein.

FIG. 147 illustrates an exploded view of an optical image stabilization(OIS) system including balanced bimorph actuators and multiple centeringsprings according to an embodiment. The optical image stabilizationsystem includes an auto focus (AF) actuator 400 having four AF solderconnections 402 or other electrical connections that pass currentbetween the AF actuator 400 and a focus control circuit. For someembodiments, the auto focus actuator 400 includes one or more SMAactuators such as those disclosed herein. The AF actuator 400, accordingto some embodiments, is disposed on a base 404 that is coupled with theAF actuator 400. The base 404 includes four isolated sections, accordingto some embodiments, with each of the isolated sections attached to aspring 406 a-d. The base 404 and the springs 406 a-d, for someembodiments, are each formed from a single flat component that is splitinto four isolated sections to create four electrical flat springcircuits to control the movement of an object, for example, the X/Y axesmovement of an optical image stabilization and/or Z axis movement of anauto focus.

For some embodiments, the isolated sections of the base 404 and or thesprings 406 a-d are formed using an etching process or othermanufacturing technique such as those known in the art. To form the fourflat spring circuits, the springs 406 a-d are welded to the base 404such that each one of the four springs 406 a-d is welded to one of thefour isolated sections of the base 404. The welds, for some embodiments,are at weld points 408 a-d included on each of the four flat springcircuits secure the springs 406 a-d to the isolated sections of the base404 to create four isolated electrical paths. For some embodiments, thefour isolated electrical paths are configured to be used for a closedloop AF. Four OIS solder connections 410 a-d are configured to connectthe flat spring circuits to the OIS control circuit included in thebimorph OIS actuator 412. The OIS control circuit is configured toconnect to the printed circuit board (PCB) to enable a camera controlcircuit to operate an AF actuator 400 and an OIS actuator 412, such asembodiments disclosed herein.

FIG. 148 illustrates a top view of an OIS system including four flatspring circuits. The flat spring circuits 414 a-d, according to someembodiments, are configured as a stainless steel (SST) circuit to enablea low cost solution for controlling movement of an image sensor. Forsome embodiments, the flat spring circuits 414 a-d are formed of 100micrometer stainless steel that is gold plated. The stiffness of thesprings including the flat spring circuits 414 a-d enable a reliable andsteady spring force that can be used for centering the AF actuator withrespect to an image sensor or otherwise controlling movement of the AFactuator. The spring 416 a-d included in the flat spring circuits 414a-d is configured to produce low stress during large changes inmovement, for example movement in a positive or negative direction in anx axis and or a y axis. For example, for some embodiments, the maximumstress on a spring during stroke motions of 330 microns is 425megapascals (Mpa). Minimizing the stress on the spring extends theusable life (e.g., have a fatigue below the infinite fatigue limit of<638 MPa) thereby improving the reliability of the OIS system over othermotion control solutions. The spring also is configured to provide adown force on the bearings of a support assembly (e.g., bearings) toprovide near zero dynamic tilt impact on an AF module and or an OIS.

FIG. 149 illustrates a base including four springs. The springs 418 a-d,according to an embodiment, are free formed to create a preload (e.g.,the springs may be free formed to have the free end of the spring extendfrom the base by 6.4 millimeters (mm) in a positive or a negativedirection in a z-axis). For some embodiments, a spring is free formed tohave a preload in a range including 15-35 millinewtons. The preload of aspring in an OIS system is configured to ensure a moving mass, such asan AF actuator, is held against one or more bearings.

Free forming the spring 418 a-d may reduce the deflection of the spring418 a-d (e.g., the deflection of the spring is reduced to plus or minus0.1 mm) to reduce the overall height requirement of the flat springcircuit, for example the amount of space in the z axis required forproper operation. FIG. 150 illustrates the spring 429 after it has beenwelded to the base to create the flat spring circuit. One or moreflattening bends in the spring may be formed in the spring before freeforming the spring. For some embodiments a spring 429 includes aflattening bend near each end of the spring 429. For example, a springincludes a first flattening bend 430 configured to have a bend in anegative direction, for example a negative 3.5 degrees in a z-axis, andor a second flattening bend 431 configured to have a bend in a positivedirection, for example a positive 3.5 degrees in a z-axis. For someembodiments, the flattening bend is in a range including 0 degrees toplus or minus 7 degrees. Other embodiments of the spring includeflattening bends configured to have bends in a range as desired to meetdesign constraints. The one or more flattening bends of the springenable the spring to achieve a downforce (e.g., +/−25 microNewtons (mN))while minimizing the amount of spring deflection (e.g., <0.1 mm of armdeflection under normal conditions and <0.2 mm of arm deflection at fullspring height). The one or more flattening bends of the spring alsoconfigure the spring to move in one direction (e.g., a positive z-axisdirection) to minimize the clearance space required below the flatspring circuit. Minimizing the amount of spring deflection andminimizing the spring deflection in a positive z-axis direction reducesthe amount of space occupied by the flat spring circuit (e.g., +/−0.2 mmin the z-axis). Accordingly, flattening one or more bends of the springin the flat spring circuit minimizes the impact of the OIS actuator onthe overall camera height enabling the assembly of smaller and morecompact electronic camera systems.

FIG. 151 illustrates a bimorph actuator including a crimp according toan embodiment. According to various embodiments, a bimorph actuator 1512includes a beam 1514, such as those described herein, and one or moreSMA materials 1516 such as an SMA ribbon or SMA wire 1516. For someembodiments, the SMA material, such as an SMA wire 1516, is affixed to afixed end 1518 of the bimorph actuator, such as those fixed endsdescribed herein, and to a load point end 1520 of the bimorph actuator,such as those described herein, so that the beam 1514 is between bothends where the SMA material is affixed. The fixed end 1518 includes acrimp portion 1522 configured to clamp down on a portion of the SMA wire1516 to affix the wire to the fixed end 1518. The load point end 1520includes a crimp portion 1524 configured to clamp down on a portion ofthe SMA wire 1516 to affix the wire to the load point end 1520. Forvarious embodiments, the ends of the SMA material are electrically andmechanically coupled with contacts configured to supply current to theSMA material using techniques including those known in the art.

It will be understood that terms such as “top,” “bottom,” “above,”“below,” and x-direction, y-direction, and z-direction as used herein asterms of convenience that denote the spatial relationships of partsrelative to each other rather than to any specific spatial orgravitational orientation. Thus, the terms are intended to encompass anassembly of component parts regardless of whether the assembly isoriented in the particular orientation shown in the drawings anddescribed in the specification, upside down from that orientation, orany other rotational variation.

It will be appreciated that the term “present invention” as used hereinshould not be construed to mean that only a single invention having asingle essential element or group of elements is presented. Similarly,it will also be appreciated that the term “present invention”encompasses a number of separate innovations, which can each beconsidered separate inventions. Although the present invention has beendescribed in detail with regards to the preferred embodiments anddrawings thereof, it should be apparent to those skilled in the art thatvarious adaptations and modifications of embodiments of the presentinvention may be accomplished without departing from the spirit and thescope of the invention. Additionally, the techniques described hereincould be used to make a device having two, three, four, five, six, ormore generally n number of bimorph actuators and buckle actuators.Accordingly, it is to be understood that the detailed description andthe accompanying drawings as set forth hereinabove are not intended tolimit the breadth of the present invention, which should be inferredonly from the following claims and their appropriately construed legalequivalents.

What is claimed is:
 1. An actuator comprising: a plurality of bimorpharms configured to reduce a net friction force of the plurality ofbimorph arms, wherein the plurality of bimorph arms are arranged in aninline, mirrored orientation, the inline, mirrored orientatingincluding: a first bimorph arm of the plurality of bimorph arms and asecond bimorph arm of the plurality of bimorph arms, the second bimorpharm arranged inline with the first bimorph arm such that a fixed end ofthe second bimorph arm is adjacent to a fixed end of the first bimorpharm, and a free end of the first bimorph arm is disposed opposite a freeend of the second bimorph arm.
 2. The actuator of claim 1, wherein eachof the plurality of bimorph arms includes a shape memory alloy (SMA)wire, and the SMA wires attached to the plurality of bimorph arms areconnected in series and are configured to receive current to each SMAwire to control actuation of the actuator.
 3. The actuator of claim 1,wherein the first bimorph arm is configured to have a friction forcecomponent in a direction of a fixed end of the first bimorph armparallel to a longitudinal axis of the actuator, and the second bimorpharm is configured to have a friction force component in a directionopposite to the first bimorph arm to reduce the net total friction tozero.
 4. The actuator of claim 1, comprising a single shape memory alloywire having a first end and a second end, the first end of the shapememory alloy coupled with the first bimorph arm of the plurality ofbimorph arms and the second end of the shape memory alloy coupled withthe second bimorph arm of the plurality of bimorph arms.
 5. An actuatorcomprising: a plurality of bimorph arms configured to reduce a netfriction force of the plurality of bimorph arms, wherein the pluralityof bimorph arms are arranged in a staggered orientation; wherein thestaggered orientation includes a first bimorph arm of the plurality ofbimorph arms and a second bimorph arm of the plurality of bimorph arms,wherein the second bimorph arm is staggered with the first bimorph armsuch that a longitudinal axis of the second bimorph arm is parallel to alongitudinal axis of the first bimorph arm and a fixed end of the firstbimorph arm is at an end of the actuator that is opposite from an end ofthe actuator adjacent to a fixed end of the second bimorph arm.
 6. Theactuator of claim 5, wherein the first bimorph arm is configured to havea friction force component in a direction of the fixed end of the firstbimorph arm parallel to the longitudinal axis of the first bimorph arm,and the second bimorph arm is configured to have a friction forcecomponent in a direction opposite to the first bimorph arm to reduce thenet total friction to zero.